Environmental certification: a scientific tool for sustainability. Evaluation of possible indicators for the environmental performance evaluation (EPE) of Ravenna province (Italy)

Environmental certification is becoming the main tool for application of sustainable development principles. The European Regulation Emas and the international standard ISO 14001 both require for certification, to perform an environmental management system to prevent environmental impacts and to continuously improve environmental performance. For a good environmental performance evaluation (EPE), certification needs to use scientific methodologies and to interface with scientific research; here we proposed emergy analysis as a valid method for EPE and emergetic environmental performance and condition indicators (EPIs, ECIs) to monitor a territorial system: Ravenna province (Italy). Together with emergy indicators were selected other indicators for a deeper EPE: emitted/adsorbed CO2, energy consumptions, air and water pollution measures. The paper showed that Ravenna system has a good environmental performance and demonstrated how different indicators from the most advanced chemical research (chemical-physical, analytical, etc.) contribute to a complete EPE of a complex territorial system and are useful for environmental certification and sustainable development.     

Thermal behavior of holo- and hemicellulose obtained from rice straw and bagasse

Thermal gravimetric analysis, and differential thermal behavior of holo- and hemicelluloses obtained from rice straw and bagasse were investigated. Degradation was found to be of first order reaction. The activation energy values and the rate constants were calculated from the kinetic of weight loss. Hemicellulose was found to be less stable than holocellulose, and the stability of the samples was arranged in the order, rice straw holo- > bagasse holo- > rice straw hemi- > bagasse hemicellulose. Degradation of rice straw (holo- as well as hemicellulose) was performed via two exothermic processes, whereas bagasse hemicellulose combustion was completed through three exothermic processes. The magnitude and the shape of the exotherms depend, mainly, on the chemical composition of the sample.     

Second-order subdifferentials of C1,1 functions and optimality conditions

We present second-order subdifferentials of Clarke's type of C ^1,1 functions, defined in Banach spaces with separable duals. One of them is an extension of the generalized Hessian matrix of such functions in ⁿ , considered by J. B. H.-Urruty, J. J. Strodiot and V. H. Nguyen. Various properties of these subdifferentials are proved. Second-order optimality conditions (necessary, sufficient) for constrained minimization problems with C ^1,1 data are obtained.This work was partially supported by the National Foundation for Scientific Investigations in Bulgaria under contract No. MM-406/1994.     

Environmental accounting for the lagoon of Venice and the case of fishing

This paper presents the application of the eMergy evaluation, introduced by H.T. Odum as an efficient methodology of environmental accounting. The results of this analysis are a part of a wider sustainability assessment for the Province of Venice realized in 2003. Within a territorial sustainability analysis, it is necessary to implement an environmental accounting method, which is able: to precisely consider the boundaries of the investigated system (spatial scale); to arbitrarily separate the life of the investigated system into periods (temporal scale); to account for both economic and natural support to a given territorial system in order to implement a sustainable management of resources; to assess all the items supporting the system on the basis of a physical unit that is objective (while the traditional economic evaluation method is based on individual preferences, hence it is subjective). The Province of Venice is a very complex system due, on one hand, to the heavy and consolidated presence of industrial activity since the beginning of the 20th century and, on the other hand, to the principal natural ecosystem which characterizes it: the lagoon, the largest wetland in the Mediterranean Sea. The role of the lagoon, as a provider of resources and services is represented by the analysis of two aspects: the lagoon as an ecosystem on the basis of the evaluation of all flows that cyclically support its biotic activity and the lagoon as a productive system on the basis of the contribution of both natural and "economic" inputs that support human activity. In particular, the case of clam fishing will be presented to put on evidence the importance of natural inputs that are systematically neglected by the traditional accounting methodologies.     

Charge-transfer complexes as polymerization inhibitors. I. Amine–chloranil complexes as inhibitors for the radical polymerization of methyl methacrylate

Charge-transfer complexes of N,N-dimethylaniline (DMA) and triethylamine (TEA) with chloranil have been investigated as inhibitors for the sensitized polymerization of methyl methacrylate (MMA) in bulk and in solution. Complete inhibition is achieved by the complexes of both amines followed by retardation only in case of DMA. The higher inhibiting efficiency of the TEA complexes is attributed to their greater stability. The polymers formed in the presence of chloranil alone or its complexes with both amines are quinonoid and contain no combined nitrogen. The results support the idea that inhibition reaction involve electron transfer from the growing chains to the quinone, with formation of molecular complexes of polymeric cations and semiquinone anions. The latter are the actual inhibiting species, so that the efficiency of inhibiting depends on their concentration, which is determined by the stability of the molecular complexes formed. The inhibition reactions should accordingly be considered as oxidation–reduction processes in which the growing chains are the electron donors. The suggested mechanism affords an explanation for the great differences in the inhibiting power of a particular quinone for the polymerization of different monomers.     

Analysis of serotonin in brain microdialysates using capillary electrophoresis and native laser-induced fluorescence detection

Serotonin or 5-hydroxytryptamine (5-HT) is a major neurotransmitter in the central nervous system. In this work, a method for analyzing 5-HT in brain microdialysis samples using a commercially available capillary electrophoresis (CE) system has been developed. A pH-mediated in-capillary preconcentration of samples was performed, and after separation by capillary zone electrophoresis, native fluorescence of 5-HT was detected by a 266 nm solid-state laser. The separation conditions for the analysis of 5-HT in standard solutions and microdialysates have been optimized, and this method has been validated on both pharmacological and analytical bases. Separation of 5-HT was performed using a 80 mmol/L citrate buffer, pH 2.5, containing 20 mmol/L hydroxypropyl-beta-cyclodextrin (HP-beta-CD) and +30 kV voltage. The detection limit was 2.5 x 10(-10) mol/L. This method allows the in vivo brain monitoring of 5-HT using a simple, accurate CE measurement in underivatized microdialysis samples.     

Molecular tectonics. Selective exchange of cations in porous anionic hydrogen-bonded networks built from derivatives of tetraphenylborate

Tetraphenylmethanes with multiple hydrogen-bonding sites are known to associate to form robust porous supramolecular networks. Analogous anionic networks can be built from the corresponding tetraphenylborates. Crystallization of the tetraphenylphosphonium salt of tetraphenylborate 2 produces an anionic network in which 74% of the volume is available for including cations and neutral guests. Other salts of anion 2 with diverse cations crystallize consistently to form the same network, whereas a neutral analogue of anion 2, tetraphenylmethane 1, produces an uncharged network that is far less open. Cations can be exchanged in single crystals of salts of tetraphenylborate 2 with retention of crystallinity and with selectivities similar to those observed in typical zeolites. Together, these observations provide new strategies for making ordered molecular materials by design, and they reveal that constructing such materials from charged subunits offers special advantages.     

2,5‐Dicarboxy­anilinium chloride monohydrate

The title compound, C₈H₈NO₄⁺·Cl⁻·H₂O, is the chloro­hydrated form of 2‐amino­benzene‐1,4‐dicarboxylic acid, the basic crystal structure of which is still not known. Mol­ecules are linked by classical N—H⋯O, O—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds, mainly along the mol­ecular plane, into sheets built by unusual R₆⁴(26), R₆⁴(22) and R₄³(22) rings. The stacking between layers is stabilized by another N—H⋯Cl hydrogen bond and by π–π inter­actions between aromatic rings facing each other.     

Anomalous NMR behavior of meso compounds with remote stereogenic centers on addition of chiral shift reagent or chiral solvating agent

A problem has arisen in using chiral shift reagents (CSR) and chiral solvating agents (CSA) to determine meso and racemic forms of diastereoisomers in which the stereogenic centers of the molecules are separated by achiral spacers. It is found that NMR signals of both meso and racemic forms of diastereoisomers may exhibit doubling on addition of CSR/CSA, which means that unequivocal assignments cannot be made without characterizing the effects for separate meso and racemic forms; this is particularly important for additions of CSR/CSA at relatively low concentrations, which always result in the splitting of some NMR signals of diastereoisomers. The phenomenon is demonstrated in the (31)P NMR spectra of meso and racemic forms of three spermine-bridged gem-disubstituted cyclotriphosphazatrienes, 1a-c, and compared with analogous achiral molecules, the per-substituted spermine-bridged cyclotriphosphazatrienes 2a-d. As expected, only one set of (31)P NMR signals was observed for the achiral compounds 2a-d, even on addition of CSA. Two sets of (31)P NMR ABX multiplets corresponding to meso and racemic diastereoisomers were observed for compounds 1a-c; on addition of CSA, the signals of at least one of the multiplets for each compound separated into more than the expected groups of three lines with an intensity distribution of 2:1:1. To understand this phenomenon, the meso and racemic forms of 1a and 1b and the meso form of 1c have been separated and characterized by X-ray crystallography. On addition of CSA to the racemic forms of 1a and 1b, the (31)P NMR spectrum shows the expected doubling of signals, but, unexpectedly, the same is observed for each of the meso forms of 1a-c. Analogous results using both CSA and CSR have been obtained for the meso and racemic forms of the diastereoisomeric piperazine-bridged macrocyclic-phosphazene compound, 3, whereas no effect was observed for the two meso forms of the doubly bridged macrocyclic-phosphazene compound 4. The phenomenon of doubling of the (31)P NMR signals of the meso form of singly bridged cyclotriphosphazatrienes, 1a-c and 3, is explained by consideration of the equilibrium in solution of independent complexation of a chiral ligand with molecules that have two chiral cyclophosphazene moieties separated by an achiral spacer group. The results show that the stereogenicity of such diastereoisomeric molecules in solution cannot be characterized unequivocally by NMR measurements on addition of either CSR or CSA.     

One-pot four-component reaction: aqueous TiCl3/PhN2+-mediated alkyl radical addition to imines generated in situ

Ti(III)-induced free-radical decomposition of a phenyldiazonium salt, followed by phenyl radical iodine-atom abstraction from alkyl iodides, leads to a one-pot selective alkyl radical addition to the C-atom of imines generated in situ under aqueous acidic conditions. [reaction: see text]