Correction to: Multivariate cluster weighted models using skewed distributions

Advances in Data Analysis and Classification - In the original publication of the article, the line after equation (5) has been published incorrectly     

Equivalent detector models for the simulation of efficiency response of an HPGe detector with PENELOPE code

ABSTRACT

In this work, some ‘equivalent’ models for the simulation of efficiency response of a High-Purity Germanium (HPGe) detector, installed inside a ‘low background’ bunker in the Engineering Department of the University of Palermo, were developed. The main feature was to attribute the uncertainties of the model to only one of the parameters, the dead layer of the detector, keeping unchanged the other data provided by the manufacturer. With this technique, using the Monte Carlo PENELOPE code in the 2011 version, the efficiency response was evaluated and compared with the previous one performed with MCNP5 code.

The validation of equivalent models is performed by comparing the simulation results with that of experimental spectrometric measurements of calibrated point sources and characterized volumetric sources such as a Marinelli beaker and an air filter reduced to a ‘packet-sample’.

The use of equivalent models makes the evaluation of efficiency curves with a Monte Carlo code easier and faster, and requires only a few experimental values for validation.     

Organotin(IV) azido and mixed azidothiocyanato complex anions; A Mössbauer and vibrational spectroscopic study

Tetraphenylarsonium and tetramethylammonium salts of the complex anions Ph₃Sn(N₃)^?₂, Ph₃Sn(N₃)(NCS)^?, Me₂Sn(N₃)^2?₄ and Ph₂Sn(N₃)₂(NCS)^2?₂ have been synthesized, and the solid state configuration of the complex anions has been studied by Mössbauer and vibrational spectroscopies. Trigonal bipyramidal structures are advanced for the Ph₃Sn^IV derivatives, with equatorial SnC₃ and apical pseudohalide ligands, while the R₂Sn^IV compounds are assumed to be trans-octahedral species. The NCS^? ligands are observed to be N-bonded to Sn^IV. Conductance and PMR (for the Me₂Sn^IV compound) data suggest the presence of the complex anions also in solution phases.     

Nachweis und Bestimmung des Mangans sowie seine Trennung von anderen Elementen

Ohne Zusammenfassung     

Nachweis und Bestimmung des Eisens, sowie seine Trennung von anderen Elementen

Ohne Zusammenfassung     

Acryloylated α,/β-poly (N-hydroxyethyl)-DL-aspartamide and α,β-polyasparthydrazide. Synthesis, characterization and radiation formation of polymeric networks

 In the present study the derivatization of two water-soluble and synthetic polymers, such as α,β-poly(N-hydroxyethyl)-DL-aspartamide (PHEA) and α,β-polyasparthydrazide (PAHy), with glycidylmethacrylate (GMA) is described. This reaction allowed the introduction of double bonds in the macromolecular chains of PHEA and PAHy in order to make easier the crosslinking by a radical mechanism. Different parameters affected the reaction of derivatization, such as reaction pH, GMA concentration and reaction time. As far as PHEA is concerned the amount of GMA linked to the polymer increased until reaching a plateau. On the contrary, the reaction of PAHy with GMA proceeded with a zero order kinetics and the GMA amount in the polymer increased regularly. Some aqueous solutions of PHEA-GMA and PAHy-GMA copolymers at various GMA content were submitted to gamma radiation processing, thus obtaining crosslinked structures. The derivatization of PHEA and PAHy with GMA was a convenient method to introduce insaturations in their chains and it allowed to obtain gels at lower doses with respect to the starting polymers. Received: 2 April 1996 Accepted: 30 June 1996     

Synthesis and characterization of water-swellableα,β-polyasparthydrazide derivatives

The synthesis of a new crosslinked polymer by reaction of , -polyasparthydrazide and glutaraldehyde is reported. Different crosslinking degrees were obtained by varying the ratio between the aldehyde and the starting polymer. The crosslinked polymer was characterized by water swelling tests and thermal analysis. In particular, the crosslinking density and its effects on the glass transition temperature of the material were studied. Finally, the microstructure of the obtained polymer was observed using scanning electron microscopy.     

Synthesis and characterization of water-swellableα,β-polyasparthydrazide derivatives

, -polyasparthydrazide (PAHy) was crosslinked by glutaraldehyde to form water-swellable materials possessing a three-dimensional molecular network. Different crosslinking degrees were prepared varying glutaraldehyde/PAHy ratio and samples containing 5-fluorouracil were obtained by incorporating the drug into the polymer networks during the crosslinking reaction. All samples were characterized by swelling tests, thermal, x-ray and SEM analysis. Their microstructure was observed through scanning electron microscopy. Furthermore, for samples containing the anticancer drug,in vitro release studies were performed in pH 7.4 buffer solution.