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2.
Elisabet Öberg Andreas Orthaber Marie-Pierre Santoni Fredrick Howard Sascha Ott 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):152-158
Abstract Attempts to utilize C-ethylenic phosphaalkenes in metathesis reactions are discussed. Unprecedented reactivity is observed where the vinylphosphaalkene undergoes the first step of the catalytic cycle and cross-metathesis with the phenylmethylene moiety of Grubbs 2nd generation catalyst. However, homo-metathesis reaction to form 1,6-diphosphahexa-1,3,5-triene is not observed, presumably due to steric constraints. 相似文献
3.
Christmann U Dau H Haumann M Kiss E Liebisch P Rehder D Santoni G Schulzke C 《Dalton transactions (Cambridge, England : 2003)》2004,(16):2534-2540
The EXAFS region of vanadium K-edge XAS spectra of native vanadate-dependent bromoperoxidase (isoenzyme I) from Ascophyllum nodosum in the presence of the substrate bromide can be fitted to three shells (at 1.62, 1.73-1.78 and 1.99-2.07 A) in the first coordination sphere of vanadium plus two more distant shells at 4.1A, possibly corresponding to bromide, and 4.7 A due to light scatterers stemming from the protein pocket. Bromide does not directly bind to the vanadium centre. The XANES and the EXAFS features for the enzyme are essentially reproduced by model complexes of the general composition [VO(H(2)O)(n)(ONO)] (n= 1 or 2) where ONO is the dianion of a Schiff base from bromosalicylaldehydes (Brsal; with the Br substituent in the position 3, 4, 5 or 6) and amino acids. The 3-Brsal derivatives exhibit an outer sphere shell at 3.8 A, which is traced back to intermolecular contacts. The data obtained from EXAFS are compared to those obtained from single crystal X-ray diffraction of [VO(H(2)O)(2)(4-Brsal-gly)] and [VO(H(2)O)(2)(6-Brsal-gly)] (gly = glycinate). In the complex [VOBr(2)(ONO)']] ((ONO)' is the Schiff base from o-anisole and o-hydroxyaniline), the V-Br distance is 2.44 A. 相似文献
4.
J. Dorenbosch F. Udo J. V. Allaby U. Amaldi G. Barbiellini M. Baubillier F. Bergsma A. Capone W. Flegel F. Grancagnolo M. Jonker L. Lanceri M. Metcalf C. Nieuwenhuis J. Panman R. Plunkett C. Santoni K. Winter I. Abt F. W. Büsser H. Daumann P. D. Gall T. Hebbeker F. Niebergall P. Stähelin P. Gorbunov E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov A. Baroncelli L. Barone B. Borgia C. Bosio M. Diemoz U. Dore F. Ferroni E. Longo L. Luminari P. Monacelli S. Morganti F. de Notaristefani L. Tortora V. Valente CHARM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,41(4):567-589
A determination of sin2 θ w based on measurements of elastic scattering of muon-neutrinos and muon-anti-neutrinos on atomic electrons is described. These purely leptonic processes were studied using the CHARM calorimeter exposed to neutrino and antineutrino wide-band beams at the CERN super proton synchrotron. A total of 83±16 neutrino-electron and 112±21 antineutrino-electron events have been detected. From the measurement of the ratio of muon-neutrino and muon-antineutrino cross-sections a value of sin2 θ w =0.211±0.037 was obtained. 相似文献
5.
Gabriella Santoni Dr. Miriam Mba Dr. Marcella Bonchio Dr. William A. Nugent Cristiano Zonta Dr. Giulia Licini Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(2):645-654
The stereoselective oxidation of differently functionalised benzyl phenyl sulfides has been examined by using enantiopure TiIV trialkanolamine complexes. These complexes efficiently catalyse the sulfoxidation with good stereoselectivities. The data highlight the contribution to the stereoselectivity of steric effects and non‐covalent π–π interactions between the aromatic rings of the TiIV complex and those pertaining to the substrates. Enantiomeric excesses have been correlated with the electrostatic potential surfaces (EPS) of the reacting sulfides. The overall study leads to a mechanistic interpretation that explains the stereoselectivity of the system and dissects the role of aromatic and steric interactions in the stereoselective process. 相似文献
6.
The rational design and synthesis of organic-inorganic hybrids as functional molecular materials relies on both the careful conception of building-blocks and the strategy for their assembly. Three families of trialkoxo polyoxometalates (Lindqvist 2, Anderson 3, Dawson 4) grafted with remote terpyridine coordination sites have been synthesized to extend the available building-blocks. These new units can be combined with metal complexes that play a role as (i) chromophores toward charge-separated systems in light-harvesting devices and (ii) coordination motifs for metal-directed self-assembly toward multifunctional molecular hybrid materials. The X-ray crystal structures of polyoxometalate-terpyridine hybrids indicate distances of 21 ? and 19 ? between the two terpyridyl coordination sites in 2 and 3, respectively, with angles between the coordination vectors of 180° and 177.4°, respectively. Lindqvist 2 displays a reduction at -0.52 V vs SCE while Anderson 3 exhibits one reversible oxidation attributed to Mn(III)/Mn(IV) (+0.75 V vs SCE) and a broad wave at -1.28 V vs SCE assigned to the Mn(III)/Mn(II) reduction. Dawson 4 displays several processes on a wide range of potentials (+0.5 to -2.0 V vs SCE) centered on V(V), W(VI) and the organic ligand in order of decreasing potentials. The grafted terpyridine ligands in Anderson 3 and Dawson 4 were successfully coordinated to {PdCl}(+) and {RuCl(3)} moieties, respectively. The polyoxometalates and transition metal complexes retain their intrinsic properties in the final assemblies. 相似文献
7.
Santoni MP Hanan GS Hasenknopf B Proust A Nastasi F Serroni S Campagna S 《Chemical communications (Cambridge, England)》2011,47(12):3586-3588
A planar bis-dipyrid-2'-yltriazine (bis-dpt) bridging ligand forms dinuclear Ru(II) complexes able to store up to eight electrons upon electrochemical reduction. 相似文献
8.
Paul-Antoine Santoni Frédéric Morandini Toussaint Barboni 《Journal of Thermal Analysis and Calorimetry》2011,104(3):1005-1015
Fireline intensity is one of the most relevant quantities used in forest fire science. It helps to evaluate the effects of
fuel treatment on fire behavior, to establish limits for prescribed burning. It is also used as a quantitative basis to support
fire suppression activities. However, its measurement is particularly tricky for different reasons: difficulty in measuring
the weight of the fuel consumed in the active fire front, difficulty to evaluate the rate of spread of the fire front, and
uncertainty on combustion efficiency. In this study, an innovative and original approach to directly measure the fireline
intensity at laboratory scale is proposed. Based on the oxygen consumption calorimetry principle, this methodology is applied
here in case of spreading fires, for the first time. It allows for directly measuring the heat released by the fire front.
The results are then used to test the famous Byram’s formulation that is generally applied to determine the fireline intensity.
Combustion efficiency and effective heat of combustion results are provided. The uncertainty and the use of a full scale calorimeter
instead of a bench scale calorimeter for this study are discussed. 相似文献
9.
F. Bergsma J. Dorenbosch C. Nieuwenhuis J. V. Allaby U. Amaldi G. Barbiellini A. Capone Y. Eisenberg W. Flegel M. Jonker L. Lanceri M. Metcalf J. Panman D. Perret-Gallix R. Plunkett C. Santoni K. Winter I. Abt J. Aspiazu F. W. Büsser H. Daumann P. D. Gall T. Hebbeker F. Niebergall P. Schütt P. Stähelin P. Gorbunov E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov L. Barone B. Borgia M. Diemoz U. Dore F. Ferroni E. Longo L. Luminari P. Monacelli F. de Notaristefani E. Valente CHARM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,40(2):171-192
We present here the final results of experiments searching for neutrino oscillations, carried out by the CHARM Collaboration. The data — taking took place in 1983. The first experiment was performed by exposing two detectors simultaneously to the CERN PS low energyv µ beam. In the second experiment the full CHARM detector was exposed to the wide-band horn-focusedv µ beam of the CERN SPS. Complete details of the experiments and data reduction are presented. No statistically significant signals for neutrino oscillations were observed. Our 90% CL limits in the appearance experiment (v µ→v e ) exclude Δm 2≧0.19 eV2 for complete mixing (sin22θ=1), and sin22θ≧0.008 for the region Δm 2≧30 eV2. These results, and the limits observed for (v µ→v x ) (disappearance of (v µ), are in agreement with those of most other experiments but exclude part of the region previously reported as a possible indication ofv µ→v e oscillations. 相似文献
10.
M. Jonker F. Udo J. V. Allaby U. Amaldi G. Barbiellini A. Capone W. Flegel M. Metcalf J. Meyer F. L. Navarria J. Panman A. M. Wetherell K. Winter F. W. Büsser H. Daumann P. D. Gall E. Metz F. Niebergall K. H. Ranitzsch P. Stähelin E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov A. Baroncelli B. Borgia C. Bosio F. Ferroni E. Longo P. Monacelli F. de Notaristefani P. Pistilli C. Santoni V. Valente 《Zeitschrift fur Physik C Particles and Fields》1983,17(3):211-217
The question whether scalar-type interactions contribute to weak interactions at large momentum transfer has been investigated by a measurement of the longitudinal polarization of positive muons produced in charged-current interactions of high-energy antineutrinos with iron. At an average momentum transfer <Q 2>=4 GeV2 the muon spin is found to be oriented forward with respect to the muon momentum vector, with an average polarization of 1.10±0.24, consistent with positive helicity. A limit on scalar contributions of σs, p/σtot <7% at the 95% confidence level can be deduced. A search for violation of time reversal invariance which could manifest itself by a polarization component perpendicular to the muon production plane gave a limit of σtv/σtot <16% (95% c.l.). It is concluded that the weak leptonic charged current retains its dominant vector and axial vector structure at large momentum transfers. 相似文献