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1.
The pure state space of Quantum Mechanics is investigated as Hermitian Symmetric Kähler manifold. The classical principles of quantum mechanics (Quantum Superposition Principle, Heisenberg Uncertainty Principle, Quantum Probability Principle) and Spectral Theory of observables are discussed in this non-linear geometrical context. 相似文献
2.
Minoia C Gatti A Aprea C Ronchi A Sciarra G Turci R Bettinelli M 《Rapid communications in mass spectrometry : RCM》2002,16(13):1313-1319
A method was developed for the determination of molybdenum (Mo) in human urine by direct dilution of the sample in doubly distilled water with 1% HNO3 (v/v) and inductively coupled mass spectrometry (ICP-MS). In and Y were used as internal standards. Since (98)Mo provides a higher sensitivity, it was chosen as the reference isotope. The influence of different factors, such as sample dilution, HNO3 concentration and the stability of the analyte were evaluated. The detection limit (LOD) was assessed at 0.2 microg/L Mo, while the lower limit of quantification (LOQ) was 0.6 microg/L. Recoveries ranged between 97.2 and 100.7% from solutions containing from 10 to 50 microg/L Mo. Linear calibration curves were generated from 2.1 and 52.1 microg/L with coefficients of variation (CV ) ranging from 1.62 to 3.56%. In order to establish reference values (RV) for molybdenum, the procedure presented here was used to determine Mo in the urine of a population group living in Tuscany, Italy. 相似文献
3.
Justum Y Gatti F Lauvergnat D Nauts A Chapuisat X 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(4):649-661
For high values of the quantum number of the total angular momentum J (up to J = 20), quantum mechanical eigenstates (eigenvalues and eigenfunctions) are calculated by the method of Gatti et al. (J. Mol. Spectrosc. 181 (1997) 403) for the bending deformations of HCN and CNH. In particular, we have examined the l-type resonances in highly excited rovibrational states within the framework of a one-dimensional model, i.e. along the reaction pathway for the isomerization reaction HCN/CNH. The potential energy surface used is that of Bowman et al. (J. Chem. Phys. 99 (1993) 308). 相似文献
4.
Tecla Gasperi M.Antonietta Loreto Paolo A. TardellaElisabetta Veri 《Tetrahedron letters》2003,44(27):4953-4956
The reactions of exocyclic α,β-unsaturated γ-lactones with NsONHCO2Et and CaO produce N-(ethoxycarbonyl) spiroaziridino γ-lactones. By reaction with acetic acid these products give ring opening reaction and acetylated N-protected α-amino γ-butyrolactones are obtained. The ring opening reaction is quantitative and highly regioselective. 相似文献
5.
H. Nitsche R. C. Gatti Sh. C. Lee 《Journal of Radioanalytical and Nuclear Chemistry》1992,161(2):401-411
We have developed an analytical method for detection of239Pu in aqueous samples at concentrations as low as 10–10M. This nuclear counting technique utilizes the uranium L X-rays, which follow the alpha-decay of plutonium. Because L X-rays are specific for the element and not for the individual isotope, the isotopic composition of the plutonium sample must be known. The counting efficiency in the 11–23 keV range is determined from a plutonium standard, and the concentration of the sample is then calculated from the L X-ray count and the isotopic composition. The total L X-ray count is corrected for possible contributions from other radionuclides present as impurities by measuring the low-energy gamma-spectrum for each contaminant to establish specific photon/X-ray ratios. The ratios are important when241Pu and242Pu are measured, because the respective decay chain members produce non-U L X-rays. This new method can replace the use of labor-intensive radiochemical separation techniques and elaborate activation methods for analysis of239Pu in aqueous samples. It is also applicable for assaying plutonium in liquid wastes that pose possible hazards to the environment. 相似文献
6.
Anna Daghetti Carlo Gatti Sergio Trasatti 《Journal of Electroanalytical Chemistry》1985,196(1):179-197
Three isotherms are considered: Frumkin's Bennes' and Mohilner's. The relationship between the interaction parameters in the first two and the adsorbate activity coefficient in the last is discussed. The significance of various standard states for the definition of ΔG° ads is analysed. The operational derivation of ΔG°ads in the three cases and the relationship between the resulting three quantities are illustrated. The isotherms have been used to describe the adsorption of 1,4-dioxane on a polarized Hg electrode. The analysis has been carried out both at constant potential and constant charge. The picture emerging in each of the three cases is discussed in the light of the results obtained in the other two. It is concluded that the three approaches give the same qualitative information about the interfacial behaviour of dioxane, especially as far as the effect of the electric field and the particle-particle lateral interaction are concerned. The usefulness of the Frumkin isotherm for analysing promptly experimental adsorption data is thus maintained. Limitations of the present approach are discussed. 相似文献
7.
M.Antonietta Loreto Lucio Pellacani Paolo A Tardella Elena Toniato 《Tetrahedron letters》1984,25(38):4271-4274
Ethoxycarbonylnitrene (EtOCON) generated by α-elimination adds cleanly to allylic ethers giving substituted aziridines. Similar addition via nitrenium ion (EtOCONH+) gives derivatives of β-amino alcohols. 相似文献
8.
The reaction of (α-trimethylsilanylmethyl)cyclohexylidene esters with NsONHCO2Et and CaO produces the N-(ethoxycarbonyl)spiroaziridines which, after ring-opening, gives the corresponding β,β-disubstituted β-amino ester derivatives. The stereochemical outcome of the reaction is influenced by substituents on the cyclohexyl group. 相似文献
9.
Maria Antonietta Zoroddu Roberto Dallocchio Maria Antonietta Cabras 《Transition Metal Chemistry》1987,12(4):356-358
Summary Copper(II) complexes with 6-benzylaminopurine (BAPH) of the types Cu(BAPH)2(ClO4)2·2H2O (1) Cu(BAP)2·4H2O (2), and Cu(BAPH2)Cl3·MeOH (3), have been synthesized and characterized by conductivity, magnetic measurements, i.r., electronic and e.s.r. spectroscopy. 相似文献
10.
Agnese Abate Elisabetta Brenna Giovanni Fronza Claudio Fuganti FrancescoG. Gatti Stefano Serra Enrica Zardoni 《Helvetica chimica acta》2004,87(4):765-780
All the enantiomerically enriched stereoisomers of Clarycet ® ( 1 ), Florol ® ( 2 ), and Rhubafuran ® ( 3 ) were prepared by biocatalysis routes. Their absolute configurations were established, and their olfactory properties were fully evaluated. 相似文献