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101.
Domenico Finco 《Reports on Mathematical Physics》2007,59(3):379-388
We discuss the asymptotic wave function of a quantum system in ?3 composed by heavy and light particles, in the case where the light particles are in scattering states and no interaction is assumed among particles of the same kind. We first review a recent result concerning the case of K heavy and N light particles, where the one-particle potential acting on each heavy particle decays at infinity. Then we consider the case of one light particle interacting with a system of harmonic oscillators and prove the same kind of result following, with some modification, the proof of the previous case. A possible application to the analysis of the scattering of a light particle from condensed matter is also outlined. 相似文献
102.
Antonino Mazzaglia Domenico Garozzo Raffaello Romeo 《Journal of organometallic chemistry》2005,690(8):1978-1985
MALDI and ESI-MS have been applied to the characterization of the reaction products between the labile cis-[Pt(DMSO)2Cl2] (1) and trans-[Pt(DMSO)2Cl(CH3)] (2) complexes with the simplest poly(amidoamine) ligand (PAMAM, G = 0, 1,2-diaminoethane as core). The comparison of the mass spectra of the starting G0 and those of the metallo-dendrimers formed upon mixing of the reagents in an equimolecular ratio, and the analysis of the isotopic distribution in the ESI spectra, have revealed the formation of cationic and neutral mononuclear complexes with PAMAM as ligand, e.g., cis-[Pt(DMSO)(PAMAM)Cl]Cl or trans-(C,N)[Pt(DMSO)(PAMAM)Cl(CH3)], together with various minor components, which have been identified as derivatives from defective structures of PAMAM. The geometry of the main products has been deduced from the values of the protons coupling constants with the isotopically abundant 195Pt. The metal-to-ligand bond is restricted to the peripheral amino groups of PAMAM which shows sufficient flexibility to involve either one or two branches in the coordination bonding. 相似文献
103.
Domenico Spinelli Anlonino Corrao Vincenzo Frenna Nicol
Vivona Michele Ruccia Giuseppe Cusmano 《Journal of heterocyclic chemistry》1976,13(2):357-360
The rates of the mononuclear heterocyclic rearrangement of the phenylhydrazone of 3-benzoyl-5-phenyl-1,2,4-oxadiazole (1) into 2,5-diphenyl-4-benzoylamino-1,2,3-triazole (II) have heen measured in dioxane/water (50:50, v:v) in the range of pS+ 3.8–12.2 at various temperatures and the activation parameters determined. On the basis of the results obtained, we present evidence for the occurrence of two different types of reaction: the first, base-catalyzed; the second, pS+ -independent. In the base-catalyzed range the catalysis is of the general type. 相似文献
104.
Kamol Dey Silvia Agnelli Federica Re Domenico Russo Gina Lisignoli Cristina Manferdini Simona Bernardi Elena Gabusi Luciana Sartore 《Macromolecular bioscience》2019,19(8)
Rational design and development of tailorable simple synthesis process remains a centerpiece of investigational efforts toward engineering advanced hydrogels. In this study, a green and scalable synthesis approach is developed to formulate a set of gelatin‐based macroporous hybrid hydrogels. This approach consists of four sequential steps starting from liquid‐phase pre‐crosslinking/grafting, unidirectional freezing, freeze‐drying, and finally post‐curing process. The chemical crosslinking mainly involves between epoxy groups of functionalized polyethylene glycol and functional groups of gelatin both in liquid and solid state. Importantly, this approach allows to accommodate different polymers, chitosan or hydroxyethyl cellulose, under identical benign condition. Structural and mechanical anisotropy can be tuned by the selection of polymer constituents. Overall, all hydrogels show suitable structural stability, good swellability, high porosity and pore interconnectivity, and maintenance of mechanical integrity during 3‐week‐long hydrolytic degradation. Under compression, hydrogels exhibit robust mechanical properties with nonlinear elasticity and stress‐relaxation behavior and show no sign of mechanical failure under repeated compression at 50% deformation. Biological experiment with human bone marrow mesenchymal stromal cells (hMSCs) reveals that hydrogels are biocompatible, and their physicomechanical properties are suitable to support cells growth, and osteogenic/chondrogenic differentiation, demonstrating their potential application for bone and cartilage regenerative medicine toward clinically relevant endpoints. 相似文献
105.
Cafarchia C Otranto D Campbell BE Latrofa MS Guillot J Gasser RB 《Electrophoresis》2007,28(8):1176-1180
Members of the genus Malassezia are budding yeasts, characterized by a thick cell wall. Recently, these yeasts have received attention as emerging pathogens. They are common commensals on the skin of animals and can become pathogenic under the influence of various predisposing factors. Central to studying their taxonomy, systematics, and ecology and to diagnosis is the accurate identification of species or operational taxonomic units. To overcome the limitations of current phenotypic and biochemical methods of identification, a PCR-coupled SSCP approach, utilizing sequence variation (0.4-33.5%) in short regions (approximately 250-270 bp) of the first internal transcribed spacer (ITS-1) of nuclear ribosomal DNA and the chitin synthase-2 gene (chs-2), was assessed for the identification and differentiation of different species/genotypes of Malassezia, characterized previously by DNA sequencing. Genomic DNA samples (n = 30) from Malassezia isolates cultured from canine skin scrapings were assessed by SSCP analysis of the two different genetic loci, and unequivocal delineation between genotypes and species was achieved. This SSCP approach is considered to provide a practical tool for the rapid and reliable genetic characterization of Malassezia genotypes/species from dogs and for investigating their population genetics and ecology. It will also provide a powerful tool for studies of Malassezia isolates from other animal species. 相似文献
106.
Condensation of ruthenium vapour with a mixture of pentane and buta-1,3-diene vapours at ?196°C, followed by warming to ?40°C, yields an unstable brown solution which reacts above ?40°C with PF3, CO or (CH3)3 CNC to give the corresponding complex [RuL(η4-C4H6)2] in > 40% yield. The ease of isolation and purification of these air sensitive complexes decreases in the order PF3 > (CH3)3CNC > CO. 相似文献
107.
Lucarini M Franchi P Pedulli GF Gentilini C Polizzi S Pengo P Scrimin P Pasquato L 《Journal of the American Chemical Society》2005,127(47):16384-16385
ESR spectroscopy has been used to study the interaction of para-pentylbenzyl hydroxyalkyl nitroxide with the monolayer of water-soluble protected gold clusters having a core diameter ranging from 1.6 to 5.3 nm. The solubilization of the nitroxide probe in the more hydrophobic environment of the monolayer strongly depends on the size of the gold core. In particular, the partition equilibrium constant increases as the nanoparticle diameter decreases. These results have been attributed to the different packing of the chains in the monolayer resulting from the different radius of curvature of the investigated nanoparticles. This represents, to the best of our knowledge, the first report demonstrating that the core size of metallic nanoparticles affects the solvating properties of the protective organic monolayer. 相似文献
108.
Alessandro Stroppa Paolo Barone Domenico Di Sante Mario Cuoco Silvia Picozzi Myung‐Hwan Whangbo 《International journal of quantum chemistry》2016,116(20):1442-1450
In developing physical theories, analogical reasoning has been found to be very powerful, as attested by a number of important historical examples. An analogy between two apparently different phenomena, once established, allows one to transfer information and bring new concepts from one phenomenon to the other. Here, we discuss an important analogy between two widely different physical problems, namely, the Jahn–Teller distortion in molecular physics and the Rashba spin splitting in condensed matter physics. By exploring their conceptual and mathematical features and by searching for the counterparts between them, we examine the orbital texture in Jahn–Teller systems, as the counterpart of the spin texture of the Rashba physics, and put forward a possible way of experimentally detecting the orbital texture. Finally, we discuss the analogy by comparing the coexistence of linear Rashba + Dresselhaus effects and Jahn–Teller problems for specific symmetries, which allow for nontrivial spin and orbital textures, respectively. 相似文献
109.
Marotta E Lapolla A Fedele D Senesi A Reitano R Witt M Seraglia R Traldi P 《Journal of mass spectrometry : JMS》2003,38(2):196-205
The Maillard reaction occurring between sugars and amino groups is important in living systems. When amino groups belonging to protein chains are involved, the Maillard reaction has been invoked as responsible for protein cross-linking and the production of 'toxic' compounds. The reaction leads to the production of a heterogeneous group of substances, usually called advanced glycation end products (AGEs). Classical analytical approaches, such as spectroscopic (ultraviolet, fluorescence) and mass spectrometric (matrix-assisted laser desorption/ionization, liquid chromatography/electrospray ionization mass spectrometry) methods, have shown that the digestion mixture is highly complex. However, there are clear differences between the digestion mixtures of glycated and unglycated human serum albumin (HSA). In the former case, possible glycated peptides belonging to the AGE peptide class may be identified. Tandem mass spectrometric experiments on selected species seemed to be promising as regards structural information, but it was thought of interest to undertake the present investigation, based on liquid chromatography/electrospray ionization Fourier transform mass spectrometry, in order to obtain definitive results on their elemental composition. Using this approach, about 20 glycated peptides were detected and their possible structures were postulated by examining the known sequence of HSA. 相似文献
110.
Amendola V Rizzi GA Polizzi S Meneghetti M 《The journal of physical chemistry. B》2005,109(49):23125-23128
Gold nanoparticles are synthesized by laser ablation of a gold plate in toluene. The nanoparticles do not show their characteristic surface plasmon absorption (SPA) and are found to be included in a graphitic matrix. The absence of this absorption is found to derive from the presence of the matrix which prevents the growth of large nanoparticles and covers them, suppressing the SPA according to the Mie model for core@shell particles. It is possible to recover the nanoparticle SPA by oxidizing the carbon matrix, obtaining, therefore, some control on the activity of this absorption. 相似文献