Characterization of raw and stabilized waste in relation to toxic metals mobility in realistic landfilling scenarios

Toxic metal release in simple leaching tests has been studied in this paper to assess waste behaviour in realistic landfilling scenarios. The waste is a galvanic sludge, raw or cement stabilized. Six different leachants were taken into account: distilled water, CO2-saturated solution, Olsen solution, Mehlich No. 3 solution, acid or alkaline soil circulating solution. Dynamic leaching tests of different duration were used for raw and stabilized waste. The results have shown that, with the exception of Mehlich No. 3 solution, when the waste comes into contact with waters of composition similar to that of the solutions studied, the potential environmental contamination should not be of concern.     

Analysis of Simulated Fluorescence Intensities Decays by a New Maximum Entropy Method Algorithm

A new algorithm for the Maximum Entropy Method (MEM) is proposed for recovering the lifetime distribution in time-resolved fluorescence decays. The procedure is based on seeking the distribution that maximizes the Skilling entropy function subjected to the chi-squared constraint χ ²?~?1 through iterative linear approximations, LU decomposition of the Hessian matrix of the lagrangian problem and the Golden Section Search for backtracking. The accuracy of this algorithm has been investigated through comparisons with simulated fluorescence decays both of narrow and broad lifetime distributions. The proposed approach is capable to analyse datasets of up to 4,096 points with a discretization ranging from 100 to 1,000 lifetimes. A good agreement with non linear fitting estimates has been observed when the method has been applied to multi-exponential decays. Remarkable results have been also obtained for the broad lifetime distributions where the position is recovered with high accuracy and the distribution width is estimated within 3 %. These results indicate that the procedure proposed generates MEM lifetime distributions that can be used to quantify the real heterogeneity of lifetimes in a sample.     

On the general form of the law of dynamics

The dynamics of Lagrangian systems is formulated with a differential geometric approach and according to a new paradigm of the calculus of variations. Discontinuities in the trajectory, non-potential force systems and linear constraints are taken into account with a coordinate-free treatment. The law of dynamics, characterizing the trajectory in a general non-linear configuration manifold, is expressed in terms of a variational principle and of differential and jump conditions. By endowing the configuration manifold with a connection, the general law is shown to be tensorial in the velocity of virtual flows and to depend on the torsion of the connection. This result provides a general expression of the EULER-LAGRANGE operator. POINCARÉ and LAGRANGE forms of the law are recovered as special cases corresponding, respectively, to the connection induced by natural and mobile reference frames. For free motions, the geodesic property of the trajectory is directly inferred by adopting the LEVI-CIVITA connection induced by the kinetic energy.     

High-throughput synthesis of HepDirect prodrugs of nucleoside monophosphates

A high-throughput phosphoramidite method for HepDirect prodrug synthesis was optimized on seven representative nucleosides, adenosine, inosine, guanosine, uridine, cytidine, AICA-riboside, and thymidine, each on a 5 mg scale. The variables optimized included (1) reaction time, (2) reaction temperature, (3) activating agent, (4) solvent, (5) purification method, and (6) stoichiometry. Preparative HPLC with mass-based fraction collection and yield determination from an ELSD standard curve enabled high-throughput. The optimized conditions for the representative nucleosides required 6 mol equiv of phosphoramidite to nucleoside and resulted in an average HPLC determined yield of 31 +/- 14% and HPLC purity of 93 +/- 3%.     

A Tutorial on Computational Cluster Analysis with Applications to Pattern Discovery in Microarray Data

Microarrays offer unprecedented possibilities for the so-called omic, e.g., genomic and proteomic, research. However, they are also quite challenging data to analyze. The aim of this paper is to provide a short tutorial on the most common approaches used for pattern discovery and cluster analysis as they are currently used for microarrays, in the hope to bring the attention of the Algorithmic Community on novel aspects of classification and data analysis that deserve attention and have potential for high reward. R. Giancarlo is partially supported by Italian MIUR grants PRIN “Metodi Combinatori ed Algoritmici per la Scoperta di Patterns in Biosequenze” and FIRB “Bioinformatica per la Genomica e la Proteomica” and Italy-Israel FIRB Project “Pattern Discovery Algorithms in Discrete Structures, with Applications to Bioinformatics”. D. Scaturro is supported by a MIUR Fellowship in the Italy-Israel FIRB Project “Pattern Discovery Algorithms in Discrete Structures, with Applications to Bioinformatics”.     

A Newtonian tale details on notes and proofs in Geneva edition of Newton's Principia

Based on our research regarding the relationship between physics and mathematics in HPS, and recently on Geneva Edition of Newton's Philosophiae Naturalis Principia Mathematica (1739–42) by Thomas Le Seur (1703–70) and François Jacquier (1711–88), in this paper we present some aspects of such Edition: a combination of editorial features and scientific aims. The proof of Proposition XLIII is presented and commented as a case study.     

Quantization of the dipole moment and of the end charges in push-pull polymers

A theorem for end-charge quantization in quasi-one-dimensional stereoregular chains is formulated and proved. It is a direct analog of the well-known theorem for surface charges in physics. The theorem states the following: (1) Regardless of the end groups, in stereoregular oligomers with a centrosymmetric bulk, the end charges can only be a multiple of 12 and the longitudinal dipole moment per monomer p can only be a multiple of 12 times the unit length a in the limit of long chains. (2) In oligomers with a noncentrosymmetric bulk, the end charges can assume any value set by the nature of the bulk. Nonetheless, by modifying the end groups, one can only change the end charge by an integer and the dipole moment p by an integer multiple of the unit length a. (3) When the entire bulk part of the system is modified, the end charges may change in an arbitrary way; however, if upon such a modification the system remains centrosymmetric, the end charges can only change by multiples of 12 as a direct consequence of (1). The above statements imply that-in all cases-the end charges are uniquely determined, modulo an integer, by a property of the bulk alone. The theorem's origin is a robust topological phenomenon related to the Berry phase. The effects of the quantization are first demonstrated in toy LiF chains and then in a series of trans-polyacetylene oligomers with neutral and charge-transfer end groups.     

Copper(I) complexes of nitrogen-sulphur ligands. 1-Phenyl-4,6-dimethylpyrimidine-2-thione and its protonated form as ligands in copper(I) complexes. Chemical,spectroscopic, conductivity and polarographic studies

Summary 1-Phenyl-4,6-dimethylpyrimidine-2-thione (L) and its protonated cation 1-phenyl-4,6-dimethyl pyrimidinium-2-thione , have been employed to prepare the following copper(I) complexes: CuXL (X=Cl, Br, I, ClO₄ or BF₄), (CuX)₃L₂ (X=Cl, Br, I or SCN), (CuX)₂L₅ (X= ClO₄ or BF₄) and the zwitterionic species CuXY(LH) X=Y=Cl, Br or I; X=Br; Y=Cl; X=I; Y=Br). Chemical analysis, conductivity, and near-and far-i.r. spectroscopic data are presented and the chemical relationships between them discussed in terms of postulated dinuclear or polynuclear species for the complexes. Metalligand vibrations suggest that the neutral ligand is N, S-bidentate in its copper(I) complexes as well as S-coordinat for the cation in the zwitterionic compounds. Diagnostic i.r. bands frequencies of counterions and (Cu–X) modes indicate the coordinating character of Cl^–, Br^–, I^–, SCN^– and of ClO ₄ ^– , BF ₄ ^– (in CuXL) anions. For the chloro-complexes CuClL and (CuCl)₃L₂, salt-like species of the [CuL₂][CuCl₂] and [{Cu₂L₂Cl}_n] [CuCl₂]_n type respectively, are proposed. The polarographic data for the perchlorate complexes have shown that in dimethylformamide (DMF) solution, the prevailing species are CuClO₄L, CuClO₄L₂ and (CuClO₄)₂L₅; their overall stability constants were determined.