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991.
Margraf G Kretz T Fabrizi de Biani F Laschi F Losi S Zanello P Bats JW Wolf B Remović-Langer K Lang M Prokofiev A Assmus W Lerner HW Wagner M 《Inorganic chemistry》2006,45(3):1277-1288
Four highly soluble square-planar Cu(II) and Ni(II) complexes of siloxy-salens (2SiCu, 2SiNi) and hydroxy-salens (2Cu, 2Ni) have been synthesized. An X-ray crystal structure analysis was performed on 2SiCu, 2SiNi, and 2Ni. The compounds have been investigated by cyclic voltammetry, UV-vis-NIR spectroelectrochemistry, and EPR spectroscopy. According to these results, the monooxidized species [2SiCu]+ and [2SiNi]+ are to be classified as Robin-Day class II and III systems, respectively. Magnetic measurements on the dinuclear (PMDTA)Cu(II) complex 1Cu2 x (PF6)2 with deprotonated 1,4-dihydroxy-2,5-bis(pyrazol-1-yl)-benzene (1) linker revealed antiferromagnetic coupling between the two Cu(II) ions thereby resulting in an isolated dimer compound. Coordination polymers [1Cu]n(H2O)(2n) of Cu(II) ions and bridging p-hydroquinone linkers were obtained from CuSO4 x 5 H2O and 1,4-dihydroxy-2,5-bis(pyrazol-1-yl)benzene. X-ray crystallography revealed linear chains running along the crystallographic a-direction and stacked along the b-axis. Within these chains, the Cu(II) ions are coordinated by two pyrazolyl nitrogen atoms and two p-hydroquinone oxygen atoms in a square-planar fashion. 相似文献
992.
Innocenti M la Marca G Malvagia S Giaccherini C Vincieri FF Mulinacci N 《Rapid communications in mass spectrometry : RCM》2006,20(13):2013-2022
This work is focused on the recovery and structural characterisation of bioactive compounds from SOR (solid olive residue), a low cost and widely available by-product in the Mediterranean basin. In the light of the interesting biological activities attributed both to secoiridoid and phenylpropanoids, the aim of this work was to carry out a systematic tandem mass spectrometric study for the identification and characterisation of these two class of compounds extracted from SOR derived from Coratina, a cultivar widely diffused in the south of Italy. Five phenylpropanoids, in addition to verbascoside, and two new secoiridoids were identified. 相似文献
993.
In this study, one random and four site-directed conjugation strategies were applied to immobilize an mAb, which stereoselectively binds to L-amino acids, onto silica particles. The resulting chiral stationary phases (CSPs) were used for enantiomer separation of the model-analyte D,L-phenylalanine and further examined in frontal affinity chromatography. Although random immobilization of the antibody onto discuccinimidyl carbonate-activated silica resulted in a CSP that enabled baseline separation of the enantiomers of D,L-phenylalanine, the amount of available binding sites was considerably lower compared to the CSPs prepared by site-directed strategies. Immobilization of antibody via its carbohydrate chains, either directly via hydrazone bonds between the support and the protein or indirectly via binding carbohydrate-biotinylated antibody to streptavidin-derivatized silica, resulted in medium column efficiencies. Higher amounts of available active sites were obtained by immobilizing the antibody indirectly through the "crystallizable fragment (Fc)" receptor protein A/G. The best results with regard to amount of available binding sites and column efficiency were obtained by first biotinylating the antibody specifically at its C-termini using carboxypeptidase Y and immobilizing the biotinylated antibody on streptavidin-derivatized silica. 相似文献
994.
Paolo Allia Marco Co?sson Paola Tiberto Franco Vinai Oana Bretcanu 《Journal of magnetism and magnetic materials》2010,322(9-12):1286-1289
Slow fluctuations of the electrical resistance R have been systematically observed in three glass-ceramics containing aggregates of magnetite nanoparticles, in measurements where R was studied as a function of time at the magnetic remanence. These fluctuations are shown to be an intrinsic (i.e., not instrumental or spurious) feature of these materials. The associated electrical noise has been obtained by performing a numerical FFT transform of different segments of the R(t) curves after proper baseline subtraction. In this way, the spectral density has been investigated in the very low-frequency region (1×10?3<f<0.2 Hz), usually not covered in standard noise measurements. The spectral density shows a 1/fα behaviour (with α?1.6) in all cases. The results are discussed in terms of the existing models about conductance fluctuations in half-metallic oxides in the hopping regime. It is suggested that electron trapping–detrapping mechanisms (thought to be the source of electrical noise) play a relevant role in the hopping processes between adjacent nanoparticle aggregates of magnetite, which dominate the material's resistivity. 相似文献
995.
Isabel Marques Rodrigues Amaral Jo?o Felipe Moreira Neto Gustavo Borges Pereira Mariani Borges Franco Marcelo Emílio Beletti Warwick Estevam Kerr Ana Maria Bonetti Carlos Ueira-Vieira 《Micron (Oxford, England : 1993)》2010,41(2):123-129
Infection in insects stimulates a complex defensive response. Recognition of pathogens may be accomplished by plasma or hemocyte proteins that bind specifically to bacterial or fungal polysaccharides. Several morphologically distinct hemocyte cell types cooperate in the immune response. Hemocytes attach to invading organisms and then isolate them by phagocytosis, by trapping them in hemocyte aggregates called nodules, or by forming an organized multicellular capsule around large parasites. In the current investigation the cellular in the hemolymph third instar larvae of M. scutellaris has been characterized by means of light microscopy analysis and phagocytosis assays were performed in vivo by injection of 0.5 μm fluorescence beads in order to identify the hemocyte types involved in phagocytosis. Four morphotypes of circulating hemocytes were found in 3rd instar larvae: prohemocytes, plasmatocytes, granulocytes and oenocytoids. The results presented plasmatocytes and granulocytes involved in phagocytic response of foreign particles in 3rd instar larvae of M. scutellaris. 相似文献
996.
Ohne Zusammenfassung 相似文献
997.
Guastello Stephen J. Orsucci Franco 《Nonlinear dynamics, psychology, and life sciences》2001,5(1):1-2
Nonlinear Dynamics, Psychology, and Life Sciences - 相似文献
998.
999.
We study the femtosecond filamentation in a liquid amplifying medium, sulphorhodamine 640 in a methanol solvent. In the presence of population inversion, the energy of the filament increases while its diameter expands because of peak intensity clamping. PACS 42.25.Bs; 42.65.Jx; 42.65.Re; 42.65.Sf 相似文献
1000.
We generalize the classical Frobenius Theorem to distributions that are spanned by locally Lipschitz vector fields. The various versions of the involutivity conditions are extended by means of set-valued Lie derivatives—in particular, set-valued Lie brackets—and set-valued exterior derivatives. A PDEs counterpart of these Frobenius-type results is investigated as well. 相似文献