56 research outputs found
Strong 3p -T1u Hybridization in Ar@C60
Multilayers of fullerenes with and without endohedral Ar units, C60 and
Ar@C60, were investigated by photoemission and density functional theory. The
stoichiometry and the endohedral nature of Ar is checked by x-ray photoelectron
spectroscopy and x-ray photoelectron diffraction. Valence band ultraviolet
photoemission spectra show a strong hybridisation of the Ar 3p valence shell
with the 6T1u molecular orbital of C60. A hybridisation gap of 1.6 +/- 0.2 eV
is found. This is in agreement with density functional theory (DFT) that
predicts 1.47 eV, and indicates Ar@C60 to be a noble gas compound with a strong
coupling between Ar and the C60 cage. No giant Ar photoemission cross section
as predicted for the gas phase in [Phys. Rev. Lett. 99, 243003 (2007)] was
found
The Assessment of the Insolvency Risk at the Companies From the Manufacturing Industry, Listed on the Bucharest Stock Exchange
The paper presents both theoretically and empirically the insolvency risk for 35 companies from the manufacturing industry in Romania, listed on the Bucharest Stock Exchange, at premium and standard categories, during 2007-2016, through four models: Springate, Taffler, Altman, and French Commercial Credit. The results of the research have revealed that during the period 2007- 2016, over 50% of the companies were facing a high insolvency risk, the most risky of them being Cemacon S.A. and Prefab S.A. The less risky companies during the mentioned period of time were Aerostar S.A. and Conted S.A
Electronic self-doping of Mo-states in A2FeMoO6 (A=Ca, Sr and Ba) half-metallic ferromagnets - a Nuclear Magnetic Resonance study
A systematic study of (A,A')2FeMoO6 (A,A'=Ca, Sr, Ba) ferromagnetic oxides
with double perovskite structure has been performed using 95,97Mo and 57Fe NMR
spectroscopy. These oxides are isoelectronic but have substantially different
Curie temperatures. The NMR analysis provides clear evidence that the magnetic
moment at Mo sites is not constant but varies sensitively with the ionic size
of the alkaline ions. The 95,97Mo frequency, and thus the electronic charge at
Mo ions, is found to be smaller in Ba and Ca than in Sr-based oxides. The
charge release from Mo sites is accompanied by an uptake at Fe sites, and thus
a self-doping Fe-Mo process is observed. This process is controlled by relevant
structural parameters: the Fe-O-Mo bond length and bending. A clear
relationship between the Curie temperature and the magnetic moment and thus
electron density at Mo sites has been disclosed. The relevance of these
findings for the understanding of ferromagnetic coupling in double perovskites
is discussed.Comment: 26 pages, 8 figure
Modified carbon-containing electrodes in stripping voltammetry of metals. Part II. Composite and microelectrodes
STUDY REGARDING THE ASSESSMENT OF THE FINANCIAL STABILITY OF THE ECONOMIC ENTITIES
The research presents both theoretical and practicalthe evolution of the financial stability assessed through the solvency indicators, the real economic growth rate and the GDP deflator in the manufacturing companies from Romania, through the Vector Autoregression Model (VAR). The sample consists in 36 companies belonging to the manufacturing industry in Romania, listed on the Bucharest Stock Exchange, on the first and second category. The study is conducted during the period 2007-2014 and demonstrated the fact that a change in the real economic growth causes a positive change in the GDP deflator. Not lastly, the change of the real economic growth also determines a positive change of the patrimonial solvency, and a change in the GDP deflator produces a reduction of the patrimonial solvency
Corrosion of titanium and zirconium under Ar irradiation in the low MeV range: an XPS and SE study
International audienc
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