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601.
A. Di Giacomo 《Physics of Atomic Nuclei》2005,68(4):554-557
The determination of the parameters of the deconfining transition in N f = 2 QCD and its relevance to the understanding of the mechanism of color confinement are discussed. 相似文献
602.
We derive the optimal universal broadcasting for mixed states of qubits. We show that the no-broadcasting theorem cannot be generalized to more than a single input copy. Moreover, for four or more input copies it is even possible to purify the input states while broadcasting. We name such purifying broadcasting superbroadcasting. 相似文献
603.
Xu M De Giacomo F Paterson DE George TG Vasella A 《Chemical communications (Cambridge, England)》2003,(12):1452-1453
The preparation of 8-substituted guanines using a new phosphorus(III)-mediated cyclisation of 4-acylamino-5-nitrosopyrimidines as the key step is described. 相似文献
604.
Wojciech?CzajaEmail author Giacomo?GiganteEmail author 《Journal of Fourier Analysis and Applications》2003,9(4):321-339
We define a continuous Gabor transform for strong hypergroups and prove a Plancherel formula, an L
2 inversion formula and an uncertainty principle for it. As an example, we show how these techniques apply to the Bessel–Kingman hypergroups and to the dual Jacobi polynomial hypergroups. These examples have an interpretation in the setting of radial functions on R
d
and zonal functions on compact two-point homogeneous spaces, where they provide a new transform which possesses many properties of the classical Gabor transform. 相似文献
605.
Renzo Ros Giacomo Facchin Augusto Tassan Raymond Roulet Gàbor Laurenczy Ferenc Lukacs 《Journal of Cluster Science》2001,12(1):99-112
The reactions of the cluster complexes [Pt3(-CO)3L3], where L=PPh3 1a, PPh2Bz 1b and PCy3 1c, with activated mono-olefins have been studied under preparative and equilibrium conditions. At low temperature the olefins react quantitatively giving the adducts [Pt3(-CO)3L3(olefin)] (olefin=trans-dicyanoethene, DCE 2a–2c, maleic anhydride, MA 3a–3c). The stereo-chemistry of these unstable clusters has been deduced from low temperature 31P, 13C, 195Pt-NMR and I.R. spectra. At higher temperature these adducts in presence of excess of olefin convert quantitatively to stable mononuclear Pt(0) complexes [Pt(CO)L(olefin)] (olefin=DCE 4a–4c, MA 5a–5c, maleimide, MI 6a–6c and 1–4-naphthoquinone, NQ 7a, 7c). 相似文献
606.
Marcello SaittaSimona Lo Curto Francesco SalvoGiuseppa Di Bella Giacomo Dugo 《Analytica chimica acta》2002,466(2):335-344
Phenolic compounds in Sicilian olive oils were analyzed by GC-MS and GC-MS/MS after extraction with methanol:water 80:20 and derivatization with bis(trimethylsilyl)trifluoracetamide and trimethylchlorosilane (BSTFA:TMCS 99:1). Numerous compounds were detected and 23 were identified. Tyrosol, hydroxytyrosol and the decarbomethoxy ligstroside and oleuropein aglycons in the dialdehydic forms were the most abundant compounds. 4-(Acetoxyethyl)-1-hydroxybenzene, 3,4-dihydroxyphenylacetaldehyde, syringaldehyde and the cis form of ferulic acid were identified: these compounds were not found in olive oils before. The presence of the dialdehydic form of elenolic acid (without carbomethoxy group) linked to 3-methoxy-4-hydroxyphenylethanol was hypothesized. There were quantitative differences in oils from the varieties Nocellara del Belice, Santagatese and Cerasuola; these differences could depend on the olive varieties and ripeness. 相似文献
607.
Giacomo Michelacci 《Geometriae Dedicata》1997,66(3):357-368
A method for the reconstruction of boundary points of convex sets is provided starting from three X-ray pictures in two orthogonal directions and from a point. 相似文献
608.
The quantity G = (α/π) Σa,μνGμνaGμνa is extracted from Monte Carlo data for SU(2) lattice gauge theory We find G = 0.015 ± 0.002 GeV4. 相似文献
609.
Tri-o-thymotide (TOT) clathrates are enantiomorphous and enantioselective (chiral cages). It was shown that an external molecular reactant can diffuse into the TOT host crystal lattice and reacts with the included molecule (guest) in characteristic ways, differing from those occurring in liquid solutions. Several aspects of the action of hydrogen halides (HCl, HBr) on the chemical behavior of included oxiranes were investigated for solid-gas and solid-liquid (aqueous) systems. Under well established experimental conditions, these reactions gave regiospecifically one target product and were asymmetric. The included substrate underwent first an acid-catalyzed allylic isomerization that is cage-specific and mostly quantitative. In sheer contrast, strong basic conditions were required to promote, in reduced yield, the analogous transformation in solution. The regiospecificity and enantioselectivity of several intra-crystalline conversions allowed the accurate determination of the absolute configuration of several guest molecules. Kinetic measurements were achieved that disclosed some striking features of this new type of heterogeneous reactions. Tentative models for the cage stereoselective mechanisms are briefly discussed. 相似文献
610.
Giacomo Picci Israel Carreira-Barral Daniel Alonso-Carrillo David Sanz-González Pablo Fernández-López María García-Valverde 《Supramolecular chemistry》2020,32(2):112-118
ABSTRACTEight N,N´-diarylisophthalamide/dipicolineamide derivatives have been synthesised and fully characterised, both in solution and in the solid state. The transmembrane anion transport properties of these compounds have been studied by chloride-selective electrode and fluorescence experiments. The substitution pattern of the aromatic moieties determines the transport properties of these systems, with those containing electron-withdrawing groups in their structures being the most active ones of the series. 相似文献