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Edoardo Reisenhofer Gianpiero Adami Andrea Favretto 《Fresenius' Journal of Analytical Chemistry》1996,354(5-6):729-734
Trace metals and nutrients were monitored voltammetrically and spectrophotometrically during a one-year period (1992/93) in the filtered fraction of coastal surface seawaters sampled with a monthly frequency at 6 different sites in the Gulf of Trieste (Northern Adriatic Sea), to evaluate the degree of pollution in an area receiving industrial, agricultural and urban wastes. The sites devoted to hatcheries of edible mussels are of particular interest. A multivariate statistical analysis of the collected concentration data by the principal component method allows to identify the sources and typology of pollution, and to discriminate between the quality of waters at the different sampling sites. The coastal waters in the Gulf of Trieste seem to be comparable to, or better than, waters of analogous areas in the Mediterranean Sea. 相似文献
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Gianpiero Cattaneo 《International Journal of Theoretical Physics》1997,36(12):3085-3117
On the basis of the concrete operations definable on the set of effect operators on a Hilbert space, an abstract algebraic
structure of sum Brouwer-Zadeh (SBZ)-algebra is introduced. This structure consists of a partial sum operation and two mappings
which turn out to be Kleene and Brouwer unusual orthocomplementations. The Foulis-Bennett effect algebra substructure induced
by any SBZ-algebra, allows one to introduce the notions of unsharp “state” and “observable” in such a way that any “state-observable”
composition is a standad probability measure (classical state). The Cattaneo-Nisticò BZ substructure induced by any SBZ-algebra
permits one to distinguish, in an equational and simple way, the sharp elements from the really unsharp ones. The family of
all sharp elements turns out to be a Foulis-Randall orthoalgebra. Any unsharp element can be “roughly” approximated by a pair
of sharp elements representing the best sharp approximation from the bottom and from the top respectively, according to an
abstract generalization introduced by Cattaneo of Pawlack “rough set” theory (a generalization of set theory, complementary
to fuzzy set theory, which describes approximate knowledge with applications in computer sciences). In both the concrete examples
of fuzzy sets and effect operators the “algebra” of rough elements shows a weak SBZ structure (weak effect algebra plus BZ
standard poset) whose investigation is set as an interesting open problem. 相似文献
88.
Boatto G Nieddu M Pirisi MA Dessì G 《Rapid communications in mass spectrometry : RCM》2007,21(22):3716-3720
A simple method for the simultaneous identification and quantification of four 2,5-methylenedioxy derivatives of 4-thioamphetamine (ALEPH series) in plasma samples was developed. The method consists of solid-phase extraction (SPE) using a Bond Elut C(18) cartridge and capillary electrophoresis coupled with electrospray ionisation mass spectrometry (CE/ESI-MS). The SPE method used required only simple steps and provided a clean extract from which identification of each drug was feasible, even at low concentrations. The method was validated according to international guidelines. The calibration curves were linear over the concentration range of 50 to 1000 ng/mL for all drugs with correlation coefficients that exceeded 0.998. The lower limits of detection of the drugs were 23-43 ng/mL. The absolute recoveries for the drugs were 64-92% and 75-96% at concentrations of 100 and 500 ng/mL, respectively. The validation data (precision, accuracy, and recovery) show the reproducibility and selectivity of the method. This clean and simple method allows the routine detection of designer drugs such as thioamphetamines which may become a serious problem in the control of illegal drugs. 相似文献
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Boatto G Culeddu N Testa C Neri B Brambilla G Barbosa J Cruz C 《Analytica chimica acta》2007,586(1-2):223-227
In animal production, it is consolidated the synthesis and the illegal use of growth promoters of new generation, able to skip routine screening and confirmatory analysis. In this work it is reported the nuclear magnetic resonance (NMR) and the mass spectrometry identification of a probable new adrenergic drug found in a feed premix. The substance was selectively purified on alpha 1 acid glycoprotein affinity columns; then its structure was first achieved by recording the 13C NMR spectrum that gave the total number of carbons of the molecule, successively sorted by DEPT experiments into quaternary, CH, CH2, and CH3 groups. However, the complete assignments of all resonances were derived from the bi-dimensional analysis and the crucial indications from the 1H-13C reverse experiments. Further characterisation was performed by atmospheric pressure chemical ionisation both in positive and negative ion mode, matching the molecular ion and the fragmentation pattern with those of most recently described new adrenergic agonists. After the loss of a ter-butylic group, the structure shows an internal symmetry along with the presence of Chlorine clusters. The proposed formula of the compound, the 8,8'-diamino-9,9'-dichloro-1-terbutyl-1,1',4,4-tetrahydro-5H,5'H-2,2'-bi-1-benzazepine-5,5'-dione, partially resembles that of Zilpaterol for the presence of a heterocyclic ring; Further work is in progress to characterise the structure-activity relationship. 相似文献
90.
Antonio Caldarelli Valeria De Biasio Giovanni B. Giovenzana Gianpiero Mastronardo Roberto Negri 《Molecular diversity》2014,18(4):879-886
Cytotoxicity in the \(\upmu \hbox {M}\) range was observed in cancer cell lines treated with N,N, \(N^{\prime }\!,\!N^{\prime }\) -tetrabenzyl-4,5-diamino-2-cyclopentenone. Cell cycle analysis on HeLa cells showed a clear G1 phase arrest. A preliminary SAR on structural analogs was performed in order to identify the pharmacophores. 相似文献