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81.
A relativistic equation for free fields whichtake their values in the Clifford algebra associatedwith the Minkowski metric is shown to be interpretableas the equation of the nucleon. The internal symmetry group SU(2) arises naturally from theassociative algebra structure of the representationspace. The latter structure can be used to constructcoupling terms consistent with the transformationproperties of the interacting fields; in particular, itallows the familiar couplings of the nucleon field withthe electromagnetic field and with the -mesonfield. 相似文献
82.
A superior, mild, high-yielding one-pot process for rapid access to oxo anilides has been developed that involves three cascade reactions: iodine-magnesium exchange, regiospecific ortho N-Fries rearrangement, and in situ trapping of the formed aniline anion. Coupled with McMurry cyclization, the two-step process allows ready synthesis of strained 1,2,3-trisubstituted indoles regioselectively. 相似文献
83.
Caprino F Moretti VM Bellagamba F Turchini GM Busetto ML Giani I Paleari MA Pazzaglia M 《Analytica chimica acta》2008,617(1-2):139-147
The present study was conducted to characterize caviar obtained from farmed white sturgeons (Acipenser transmontanus) subjected to different dietary treatments. Twenty caviar samples from fish fed two experimental diets containing different dietary lipid sources have been analysed for chemical composition, fatty acids and flavour volatile compounds. Fatty acid make up of caviar was only minimally influenced by dietary fatty acid composition. Irrespective of dietary treatments, palmitic acid (16:0) and oleic acid (OA, 18:1 n-9) were the most abundant fatty acid followed by docosahexaenoic acid (DHA, 22:6 n-3) and eicopentaenoic (EPA, 20:5 n-3). Thirty-three volatile compounds were isolated using simultaneous distillation-extraction (SDE) and identified by GC-MS. The largest group of volatiles were represented by aldehydes with 20 compounds, representing the 60% of the total volatiles. n-Alkanals, 2-alkenals and 2,4-alkadienals are largely the main responsible for a wide range of flavours in caviar from farmed white surgeon. 相似文献
84.
Poly‐l‐Lactic Acid Nanofiber–Polyamidoamine Hydrogel Composites: Preparation,Properties, and Preliminary Evaluation as Scaffolds for Human Pluripotent Stem Cell Culturing 下载免费PDF全文
Chiara Gualandi Nora Bloise Nicolò Mauro Paolo Ferruti Amedea Manfredi Maurilio Sampaolesi Anna Liguori Romolo Laurita Matteo Gherardi Vittorio Colombo Livia Visai Maria Letizia Focarete Elisabetta Ranucci 《Macromolecular bioscience》2016,16(10):1533-1544
Electrospun poly‐l ‐lactic acid (PLLA) nanofiber mats carrying surface amine groups, previously introduced by nitrogen atmospheric pressure nonequilibrium plasma, are embedded into aqueous solutions of oligomeric acrylamide‐end capped AGMA1, a biocompatible polyamidoamine with arg‐gly‐asp (RGD)‐reminiscent repeating units. The resultant mixture is finally cured giving PLLA‐AGMA1 hydrogel composites that absorb large amounts of water and, in the swollen state, are translucent, soft, and pliable, yet as strong as the parent PLLA mat. They do not split apart from each other when swollen in water and remain highly flexible and resistant, since the hydrogel portion is covalently grafted onto the PLLA nanofibers via the addition reaction of the surface amine groups to a part of the terminal acrylic double bonds of AGMA1 oligomers. Preliminary tested as scaffolds, the composites prove capable of maintaining short‐term undifferentiated cultures of human pluripotent stem cells in feeder‐free conditions.
85.
Michele Camero Mariarosaria Marinaro Michele Losurdo Vittorio Larocca Livia Bodnar Giovanni Patruno 《Natural product research》2016,30(5):605-607
Clinical score (A) and viral shedding (B) in goats vaginally infected with CpHV-1 and treated with fig latex (goats A, B, C). Goat D was left untreated. 相似文献
86.
In this article, we study the approximation of common zeros of non-self inverse strongly monotone operators defined on a closed convex subset C of a Hilbert space H. For a non-self family of operators, we introduce an iterative algorithm without relying on projections. Approximation of common fixed points for finite families of non-self strict pseudo-contractions in the sense of Browder-Petryshyn is also obtained. The novelty of our algorithm is that the coefficients are not given a priori and no assumptions are made on them, but they are constructed step by step in a natural way. 相似文献
87.
We propose a new formulation of the Karush–Kunt–Tucker conditions of a particular class of quasi-variational inequalities. In order to reformulate the problem we use the Fisher–Burmeister complementarity function and canonical duality theory. We establish the conditions for a critical point of the new formulation to be a solution of the original quasi-variational inequality showing the potentiality of such approach in solving this class of problems. We test the obtained theoretical results with a simple heuristic that is demonstrated on several problems coming from the academy and various engineering applications. 相似文献
88.
María D. Hernández-Alonso Juan M. Coronado Javier Soria José Carlos Conesa Vittorio Loddo Maurizio Addamo Vincenzo Augugliaro 《Research on Chemical Intermediates》2007,33(3-5):205-224
Oxidation of free cyanide in aqueous suspensions of three commercial TiO2 specimens, with different anatase crystal size, has been carried out in a batch photoreactor by simultaneously applying ozonation and photocatalysis. Dissolved ozone participates both in homogeneous and catalytic reactions with cyanide; the extents of these two processes are comparable to that of the photodegradation with oxygen. The reactivity results are well described by the Langmuir-Hinshelwood kinetic model, providing the values of the kinetic and equilibrium adsorption constants for the catalytic and photocatalytic reactions contributing to cyanide oxidation. The cyanide concentration decreases faster with time for catalysts with increasing anatase crystal size, being more marked under UV irradiation. EPR studies on gaseous ozone adsorption on the three samples in the dark have shown stronger ozone interactions with Ti4+ and O2? ions of the samples with largest anatase crystal size, leading to the formation of significant signals of Ti3+ and s O??O2 radicals than with the anatase with the lowest crystal size, where ozone was mainly adsorbed on water molecular arrangements covering its surface. The hampering of the ozone and/or cyanide adsorption by the water molecular arrangements covering the surface of the catalyst with the lowest crystal size would justify the low cyanide degradation rate observed for this sample. 相似文献
89.
Riccardo Destro Emanuele Ortoleva Giorgio Modena Lucia Pasquato Vittorio Lucchini 《Helvetica chimica acta》2001,84(4):860-866
Four‐membered ring thiosulfonium ions may be obtained quantitatively and under mild conditions by anionotropic rearrangement of C‐(tert‐butyl)‐substituted thiiranium ion precursors. Thus, t‐4‐(tert‐butyl)‐r‐1,2,2,c‐3‐tetramethylthietanium tetrafluoroborate or hexachloroantimonate ( 2a or 2b , resp.) were formed from thiiranium ion 1 . The thietanium salts 2a and 2b were characterized by X‐ray crystal‐structure analysis. Their cation geometry was also optimized by ab initio calculations at the RHF/6‐31G*//RHF/6‐31G* level, as were those of its stereoisomer 3 and of the unsubstituted S‐methylthietanium ion 5 . Comparison of 2 , 3 , and 5 with 4 – the only other thietanium ion studied by XRD, where the C‐atoms of the thioniacyclobutane ring are part of a trinorbornane skeleton – indicates that, in these systems, relief from substituent overcrowding is easily achieved by a folding of the four‐membered ring along the line connecting the two opposite C‐atoms. The corresponding ring‐deformation normal mode has a calculated frequency as low as 109 cm−1 in ion 5 , to be compared with a frequency of 138 cm−1 in methylcyclobutane. For thietanium ion 2 , the frequencies of the two normal modes involving such ring deformation have calculated values of 61 and 85 cm−1. 相似文献
90.
Giuseppe Bruno Francesco Nicol Fausto Puntoriero Gaetano Giuffrida Vittorio Ricevuto Giuseppe Rosace 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o390-o391
The title compound, C21H19N7, is a polypyridine ligand that is suitable for assembling complex metal systems capable of photoinduced electron transfer. The solid‐state structure has been determined at room temperature by single‐crystal X‐ray diffraction. The molecule is not flat and both the bis(pyridyl)triazole and the benzylideneamine fragments show significant distortions from planarity. 相似文献