The Cyprus Institute

About: The Cyprus Institute is a other organization based out in Nicosia, Cyprus. It is known for research contribution in the topics: Aerosol & Environmental science. The organization has 418 authors who have published 1252 publications receiving 32586 citations.

Non-destructive in situ analysis of polychromy on ancient Cypriot sculptures

Abstract: The study focuses on the characterization of polychromy on limestone sculptures from Cyprus, attributed to the Cypro-Archaic—end of the Hellenistic periods. Polychromy components were identified by integrating digital microscopy, imaging under ultraviolet (UV) light, visible-induced luminescence (VIL), X-ray fluorescence spectroscopy (XRF) and fibre optics reflectance spectroscopy (FORS). Data acquisition was performed directly in exhibition rooms at the Cyprus Museum (Nicosia) and the Paphos District Archaeological Museum (Paphos). Among the identified materials, there are iron-containing (red, yellow, green) and copper-containing (green and blue) pigments. The precision of pigment identification by non-destructive techniques is discussed, and specific pigment names are proposed: red iron oxide, yellow iron oxide-hydroxide, green earth and Egyptian blue. Interesting results were obtained by VIL, which allowed identifying traces of Egyptian blue otherwise undetectable with the naked eye. Complementary, this study discusses advantages and problems of combined and separate use of portable XRF and FORS, raising the question of their complementarity and interchangeability for the purposes of pigment identification.

Global risk from the atmospheric dispersion of radionuclides by nuclear power plant accidents in the coming decades

Abstract: . We estimate the global risk from the release and atmospheric dispersion of radionuclides from nuclear power plant accidents using the EMAC atmospheric chemistry–general circulation model. We included all nuclear reactors that are currently operational, under construction and planned or proposed. We implemented constant continuous emissions from each location in the model and simulated atmospheric transport and removal via dry and wet deposition processes over 20 years (2010–2030), driven by boundary conditions based on the IPCC A2 future emissions scenario. We present global overall and seasonal risk maps for potential surface layer concentrations and ground deposition of radionuclides, and estimate potential doses to humans from inhalation and ground-deposition exposures to radionuclides. We find that the risk of harmful doses due to inhalation is typically highest in the Northern Hemisphere during boreal winter, due to relatively shallow boundary layer development and limited mixing. Based on the continued operation of the current nuclear power plants, we calculate that the risk of radioactive contamination to the citizens of the USA will remain to be highest worldwide, followed by India and France. By including stations under construction and those that are planned and proposed, our results suggest that the risk will become highest in China, followed by India and the USA.

The low temperature D+ + H2→ HD + H+ reaction rate coefficient: a ring polymer molecular dynamics and quasi-classical trajectory study.

Abstract: The reaction between D+ and H2 plays an important role in astrochemistry at low temperatures and also serves as a prototype for a simple ion–molecule reaction. Its ground 1A′ state has a very small thermodynamic barrier (up to 1.8 × 10−2 eV) and the reaction proceeds through the formation of an intermediate complex lying within the potential well with a depth of at least 0.2 eV, thus representing a challenge for dynamical studies. In the present work, we analyze the title reaction within the temperature range of 20–100 K by means of ring polymer molecular dynamics (RPMD) and quasi-classical trajectory (QCT) methods over the full-dimensional global potential energy surface developed by Aguado et al. [A. Aguado, O. Roncero, C. Tablero, C. Sanz and M. Paniagua, J. Chem. Phys., 2000, 112, 1240]. The computed thermal RPMD and QCT rate coefficients are found to be almost independent of temperature and fall within the range of 1.34–2.01 × 10−9 cm3 s−1. They are also in very good agreement with previous time-independent quantum mechanical and statistical quantum method calculations. Furthermore, we observe that the choice of asymptotic separation distance between the reactants can markedly alter the rate coefficient in the low temperature regime (20–50 K). Therefore it is of utmost importance to correctly assign the value of this parameter for dynamical studies, particularly at very low temperatures of astrochemical importance. We finally conclude that the experimental rate measurements for the title reaction are highly desirable in future.