Search results for "cop"
showing 10 items of 25502 documents
Synthesis, Characterization of FexZr1-xO2Solid Solution Nanoparticles and Bulk Powders Prepared Using a Sol-Gel Technique
2015
Electrical Transport and Confocal Raman Studies of Electrochemically Modified Individual Carbon Nanotubes
2003
Erratum to ‘Raman spectroscopy of β-irradiated silica glass’ by B. Boizot, S. Agnello, B. Reynard, R. Boscaino and G. Petite [J. Non-Cryst. Solids 32…
2004
<title>Electrochromism of W-oxide-based films: some theoretical and experimental results</title>
1995
We survey some recent work related to electrochromic W-oxide-based thin films. The electronic structure of cubic (perovskite) WO3 and HWO3 was calculated from first principles. It was found, among other things, that hydroxide formation was energetically favored. Experimental studies were made on films prepared by reactive magnetron sputtering in Ar + O2 with and without CF4 addition and substrate bias. Structural studies by atomic force microscopy, x-ray diffraction, infrared reflectance spectroscopy, and Raman spectroscopy indicated that the electron bombardment associated with a positive substrate bias led to grain growth and partial crystallization while maintaining a high density of W e…
High Resolution Coherent Raman Spectroscopy: Studies of Molecular Structures
1992
One of the main advantages of the non-linear coherent Raman techniques is the high resolution that can be achieved in rovibrational spectroscopy. Typically an instrumental function of the order of several thousandths of a wavenumber is routinely achieved in SRS or CARS experiments. Since the first recording of the stimulated Raman spectrum of 12CH4 in 1978 [1], numerous studies of molecules have been performed [2–8]. We have built a stimulated Raman experiment in Dijon in which particular attention has been paid to the frequency measurement of the Raman lines [9]. We will describe the application of our experiment to a wide variety of molecules over the last few years: linear molecules, sph…
Phonon Deformation Potentials from Raman Measurements on Semiconductor Membranes
1997
Introduction: The Pedagogical Obstacle of the Phenomenal Forms
2016
This book is a further development from a previous one, published only in Spanish, whose title can be translated as The Copernican turn and the social sciences (Villacanas de Castro, 2013). It was a philosophical work relating to a general epistemological problem lying at the heart of the social and natural sciences. On the other hand, the present volume is firmly rooted in pedagogy. This difference reflects the professional journey that I have made in the meantime, from being a Graduate Student at a Faculty of Philosophy to becoming a member of staff at a Faculty of Education, where I currently lecture and carry out research. Despite the various shifts brought about by this transition, an …
A Place for Life
2010
The belief in the existence of extraterrestrial civilizations starts from the so-called principle of mediocrity. This principle postulates that Earth is a normal planet that rotates around a normal star, which in turn is located in a normal galaxy. That is to say, there is nothing so special in our world as to make it unique. This is a logical conclusion, toward which we are guided by the successive “Copernican turns” that science has suffered throughout its long history, and which has removed us from the central position we once believed to occupy in the universe.
Theoretical Study of the Electronic Spectrum of trans-Stilbene
1997
The electronic spectrum of trans-stilbene in the energy range up to 6 eV has been studied using multiconfigurational second-order perturbation theory (CASPT2). The study includes a geometry determination of the ground state. In all, 12 singlet and one triplet excited states were studied. The calculated spectrum makes it possible to assign the valence excited singlet states corresponding to the three bands observed in the low-energy region of the one-photon absorption spectrum. The most intense feature of the calculated spectrum corresponds to the 11Ag → 21Bu transition at 4.07 eV. The weakly allowed 11Bu state was found 0.3 eV below 21Bu. Transition to the 31Ag state, computed at 4.95 eV, i…
Optical study of gallium and nitrogen polarity layers of GaN grown on sapphire
2003
A confocal Raman spectroscopic study was carried out on either side of an intentionally grown GaN inversion domain boundary between a pair of strips with opposite (Ga- or N-) polarity. It is shown that the Raman spectra on the N-polarity side displays an A1(TO) mode, prohibited by symmetry considerations, meanwhile on Ga-polarity material this peak is absent, indicating a lower density of defects present in this region. The Raman spectra reveal that in the lateral direction, the change in structural quality accross the inversion domain boundary is rather continuous and extends along 4 ± 1 μm. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)