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101.
102.
Andrea Salvo Archimede Rotondo Valentina Mangano Teresa Gervasi Claudio Gervasi 《Natural product research》2020,34(1):172-176
AbstractThis study investigates the inorganic elements and the persistent organic pollutants (POPs) accumulated in liver of a sexually mature Hexanchus griseus living in the Mediterranean Sea. The casual finding of a specimen in the Strait of Messina (April 2018) allowed us to carefully analyse its liver which can be considered a very important biological indicator. The determination of inorganic elements was carried out by ICP-MS technique. Quantitative determination of polycyclic aromatic hydrocarbons (PAH) and poly-chloro-biphenyl compounds (PCB), distinguished in dioxine-like (DL) and not-dioxine-like (NDL) derivates, has been carried out by HRGC/MS and HRGC-MS/MS respectively. Worrying levels of PCB-DL (TEQ?=?Σ(PCB-DL)*TEF?=?5.96?ng g?1), PCB-NDL (Σ(PCB-NDL)?=?1390.4?ng g?1) together with the presence of pesticides and plasticizers were found in the shark liver oil. The levels of heavy metals were below the legal limits. 相似文献
103.
M. Assunta Girasolo Clelia Di Salvo Arturo Silvestri 《Journal of organometallic chemistry》2006,691(4):693-701
The heterocyclic ligands [1,2,4]triazolo-[1,5-a]pyrimidine (tp) and 5,7-dimethyl-[1,2,4]triazolo-[1,5-a]pyrimidine (dmtp), react with diorganotin dichlorides giving the addition compounds Me2SnCl2(tp)2, Et2SnCl2(tp)2, Me2SnCl2(dmtp)2, Et2SnCl2(dmtp)2, Bu2SnCl2(dmtp), Ph2SnCl2(dmtp). The organotin:ligand stoichiometry goes from 1:2 to 1:1 by increasing the steric hindrance of the organic groups bound to tin. The compounds have been characterized by means of infrared, 119Sn Mössbauer and 1H AND 13C NMR spectroscopy.The ligands presumably coordinate to tin classically through the nitrogen atom at the position 3. The 1:1 complexes adopt trigonal bipyramidal structures, with the organic groups on the equatorial plane and the ligand in the apical position. All-trans octahedral structures are inferred for the 1:2 complexes, except for Et2SnCl2(tp)2, characterized by a skew-trapezoidal structure.119Sn Mössbauer measurements, at room temperature, in concomitance with DFT calculations, performed on isomeric structures of R2SnCl2(tp)2 (R = Me, Et), allowed us to conclude that the all-trans octahedral coordination induces self-assembly in the solid state, possibly accomplished through π-π stacking interactions among the planar ligands coordinated to the organotin(IV) compound, while the skew-trapezoidal structure attributed to Et2SnCl2(tp)2, induces the formation of monomeric adducts in the solid state.In vitro antimicrobial tests showed that [n-Bu2SnCl2(dmtp)] has interesting properties as anti Gram-positive and antibiofilm agent. 相似文献
104.
105.
The KLOE- collaboration A. Anastasi D. Babusci G. Bencivenni M. Berlowski C. Bloise F. Bossi P. Branchini A. Budano L. Caldeira Balkest?hl B. Cao F. Ceradini P. Ciambrone F. Curciarello E. Czerwinski G. D’Agostini E. Danè V. De Leo E. De Lucia A. De Santis P. De Simone A. Di Cicco A. Di Domenico R. Di Salvo D. Domenici A. D’Uffizi A. Fantini G. Felici S. Fiore A. Gajos P. Gauzzi G. Giardina S. Giovannella E. Graziani F. Happacher L. Heijkenskj?ld W. Ikegami Andersson T. Johansson D. Kaminska W. Krzemien A. Kupsc S. Loffredo G. Mandaglio M. Martini M. Mascolo R. Messi S. Miscetti G. Morello D. Moricciani P. Moskal M. Papenbrock A. Passeri V. Patera E. Perez del Rio A. Ranieri P. Santangelo I. Sarra M. Schioppa M. Silarski F. Sirghi L. Tortora G. Venanzoni W. Wislicki M. Wolke 《Journal of High Energy Physics》2016,2016(5):19
106.
Salvo D'Agostino 《Physics in Perspective (PIP)》2000,2(4):398-410
Maxwell's and Hertz's pure-field theories, which excluded the convective conception of electric currents and the discreteness of electric particles, are illustrated in the first sections of the paper. Thereafter, I examine Lorentz's theory of electrons and contrast it with Maxwell's and Hertz's positions. I show that Lorentz was convinced that it was necessary to modify Maxwell's and Hertz's fundamental assumptions to graft onto their continuous theories the discreteness of the electron. I consider these historical cases as emblematic of a new view of the dynamics of physical theories. 相似文献
107.
O. Bartalini V. Bellini J. P. Bocquet P. Calvat A. D’Angelo J. -P. Didelez R. Di Salvo A. Fantini F. Ghio B. Girolami M. Guidal A. Giusa E. Hourany A. S. Ignatov R. Kunne A. M. Lapik P. Levi Sandri A. Lleres D. Moricciani A. N. Mushkarenkov V. G. Nedorezov C. Perrin D. Rebreyend F. Renard N. V. Rudnev T. Russew G. Russo C. Schaerf M. -L. Sperduto M. -C. Sutera A. A. Turinge 《Physics of Atomic Nuclei》2008,71(1):75-82
The total photoabsorption cross section on a free proton was measured at the GRAAL facility in the energy range E
γ = 600−1500 MeV. The large-aperture LAGRANγE detector and a liquid hydrogen target were used in the experiment performed with
a back-scattered Compton gamma beam. To improve the accuracy, two alternative methods were employed. First, a subtraction
method of using empty-target measurements allowed the cross section σ
tot to be evaluated directly because of a low level of the electromagnetic background. Second, an algorithm for evaluating σ
tot on the basis of summing the dominating partial cross sections was developed. Experimental results obtained for σ
tot by the two methods are compared with existing data.
The article was translated by the authors.
Published in Russian in Yadernaya Fizika, 2008, Vol. 71, No. 1, pp. 76–83. 相似文献
108.
Mario De Salvo Domenico Freni Giovanni Lo Faro 《Rendiconti del Circolo Matematico di Palermo》1922,46(1):29-51
In this paper one continues the study of hypergroups with for proper pairs. In particular one considers the case when the scalars group is not empty and the set of non-scalar elements has size two or three. 相似文献
109.
A Racemic and Enantiopure Unsymmetric Diiron(III) Complex with a Chiral o‐Carborane‐Based Pyridylalcohol Ligand: Combined Chiroptical,Magnetic, and Nonlinear Optical Properties 下载免费PDF全文
Dr. Florencia Di Salvo Min Ying Tsang Prof. Dr. Francesc Teixidor Prof. Dr. Clara Viñas Dr. José Giner Planas Dr. Jeanne Crassous Dr. Nicolas Vanthuyne Prof. Dr. Núria Aliaga‐Alcalde Prof. Dr. Eliseo Ruiz Prof. Dr. Gerard Coquerel Dr. Simon Clevers Dr. Valerie Dupray Dr. Duane Choquesillo‐Lazarte Dr. Mark E. Light Prof. Dr. Michael B. Hursthouse 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(4):1081-1090
The design of molecule‐based systems combining magnetic, chiroptical and second‐order optical nonlinear properties is still very rare. We report an unusually unsymmetric diiron(III) complex 1 , in which three bulky chiral carboranylpyridinealkoxide ligands ( o CB hmp?) bridge both metal ions and the complex shows the above‐mentioned properties. The introduction of o‐carborane into the 2‐(hydroxymethyl)pyridine (hmpH) architecture significantly alters the coordination of the simple or aryl‐substituted 2‐hmpH. The unusual architecture observed in 1 seems to be triggered by the poor nucleophilicity of our alkoxide ligand ( o CB hmp?). A very rare case of spontaneous resolution takes place on precipitation or exposure to solvent vapor for the bulk compound, as confirmed by a combination of single‐crystal and powder X‐ray diffraction, second‐harmonic generation, and circular dichroism. The corresponding enantiopure complexes (+) 1 and (?) 1 have also been synthesized and fully characterized. This research provides a new building block with unique geometry and electronics to construct coordination complexes with multifunctional properties. 相似文献
110.
A new concept for an infrared waveguide detector based on silicon is introduced. It is fabricated using silicon-on-insulator material, and consists of an erbium-doped p-n junction located in the core of a silicon ridge waveguide. The detection scheme relies on the optical absorption of 1.5-/spl mu/m light by Er/sup 3+/ ions in the waveguide core, followed by electron-hole pair generation by the excited Er and subsequent carrier separation by the electric field of the p-n junction. By performing optical mode calculations and including realistic doping profiles, we show that an external quantum efficiency of 10/sup -3/ can be achieved in a 4-cm-long waveguide detector fabricated using standard silicon processing. It is found that the quantum efficiency of the detector is mainly limited by free carrier absorption in the waveguide core, and may be further enhanced by optimizing the electrical doping profiles. Preliminary photocurrent measurements on an erbium-doped Si waveguide detector at room temperature show a clear erbium related photocurrent at 1.5 /spl mu/m. 相似文献