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61.
María Virginia Mirífico José Alberto Caram Ana María Gennaro Carlos J. Cobos Enrique Julio Vasini 《Journal of Physical Organic Chemistry》2011,24(11):1039-1044
Radical anions from several 3,4‐aryl‐disubstituted derivatives of 1,2,5‐thiadiazole 1,1‐dioxide were accumulated through chemical reduction of the substrates in aprotic solvents. The radical anions were characterized by electron spin resonance and cyclic voltammetry. DFT theoretical calculations were also performed for the 3,4‐diphenyl derivative. The course of the reductions was followed using cyclic voltammetry. Uncommon reductants, such as amides, were found to be effective under certain conditions. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
62.
S. Di Gennaro 《Journal of Optimization Theory and Applications》2003,116(1):41-60
In this work, we propose a dynamic controller for a spacecraft with flexible appendages and based on attitude measurements. This control ensures the asymptotic fulfillment of the objectives in the case of rest-to-rest maneuvers when a failure occurs on the accelerometer sensors, so that the angular velocity is not available for feedback. Also, it is assumed that the modal variables describing the flexible elements are not measured. This is a lower level controller and is to be selected at the higher level by a supervisor when an emergency situation is detected. 相似文献
63.
Summary Methods for the separation of food-related biogenic amines (histamine, tyramine, 2-phenylethylamine and tryptamine) have been developed based on ion-interaction reversed-phase liquid chromatography.Two different interaction reagents have been comparatively used, namely octylamine ortho-phosphate (at wave-lengths of 230, 254 and 280 nm) and octylamine salicylate (at a wavelength of 254 nm). The different elution sequence orders shown by the investigated amines for the two reagents are discussed and compared.The detection limits obtained were 20 ppb for tryptamine ( =280 nm), 500 ppb for 2-phenylethylamine (=254 nm), 400 ppb for tyramine (=230 or 280 nm) and 900 ppb for histamine (=230 nm).The method was applied to the analysis of a five years old Italian red wine, in which 2-phenylethylamine (at a concentration of 72±3 ppm) and tryptamine (at a concentration of 4.0±0.3 ppm) were found to be present. 相似文献
64.
Giorgia Oliviero Aldo Galeone Gennaro Piccialli Luciano Mayol 《Tetrahedron letters》2004,45(25):4869-4872
A cluster of four d(TG4T) hexanucleotides with the 3′-ends linked together by a bunchy spacer has been synthesized and shown to form a monomolecular parallel quadruplex 5 in solution characterized by four G-quartets. 1H NMR spectroscopy and CD thermal denaturation experiments indicate the monomolecular quadruplex (5) to be more stable than the tetramolecular counterpart [d(TG4T)]4. 相似文献
65.
Titrimetric assays for phytic acid by titration with iron(III) or thorium are described. Stannous chloride interferes in both systems, causing negative errors directly proportional to the amount of stannous chloride. The thorium:phytate ratio in the complex formed is 2:1, which is interpreted as resulting from the possession of two chelating centres by phytic acid. 相似文献
66.
Zahid Hassan Hidayat Hussain Viqar Uddin Ahmad Shazia Anjum Gennaro Pescitelli Tibor Kurtn Karsten Krohn 《Tetrahedron: Asymmetry》2007,18(24):2905-2909
The absolute configuration of 1β,10β-epoxydesacetoxymatricarin 1, a sesquiterpenoid isolated from Carthamus oxycantha, was established by TDDFT CD calculations in combination with single crystal X-ray analysis. Since the solid-state CD spectrum shows contributions from intermolecular interactions in the crystal, 1 represents a test case for our solid-state CD/TDDFT approach. 相似文献
67.
Summary Separation methods have been developed by means of reversed-phase ion-interaction HPLC chromatography, using octylamine ortho-phosphate as the interaction reagent. In particular the separation of some antioxidants of relevant interest (known also as radical scavengers) such as L(+)-ascorbic acid, uric acid, orotic acid and cysteine, as well as the separation of creatine and creatinine have been performed. The results have been applied to the analysis of different kinds of milk, namely a dairy farm milk, a commercial whole fresh milk and a UHT-sterilized one: creatinine, uric, L(+)-ascorbic and orotic acids were identified and quantified. 相似文献
68.
Purification of Phleum pratense pollen extract by immunoaffinity chromatography and high-performance ion-exchange chromatography 总被引:1,自引:0,他引:1
E Bolzacchini P Di Gennaro G Di Gregorio B Rindone P Falagiani G Mistrello I Sondergaard 《Journal of chromatography. A》1991,548(1-2):229-234
Basic allergens of Phleum pratense pollen extract have been purified by either sequence gel filtration-ion-exchange high-performance liquid chromatography (HPIEX) and size-exclusion HPLC or sequence gel filtration-immunoaffinity chromatography and HPIEX. The second procedure seems to be suitable for preparative purposes. 相似文献
69.
Concetta D'Aniello Gennaro Romano Roberto Russo Vittoria Vittoria 《Macromolecular Symposia》1999,138(1):139-147
Physical aging in polyethylene terephtalate (PET) has been studied on samples well characterized in terms of aging history and their content of water. This allows us to better understand the role played by water in the complex phenomenology of the physical aging in a hygroscopic material as PET. No appreciable changes in the thermal behavior in the sample aged in water at room temperature for one month were noted, while substantial changes were observed in samples aged in more severe conditions like 50°C under vacuum and 50°C in water for one month. The results are consistent with the formation of small regions in which segments of chains are closely packed. 相似文献
70.
Marco Fantin Francesca Lorandi Abdirisak A. Isse Armando Gennaro 《Macromolecular rapid communications》2016,37(16):1318-1322
Electrochemically‐mediated atom transfer radical polymerization (eATRP) of oligo(ethylene oxide) methyl ether methacrylate in water is investigated on glassy carbon, Au, Ti, Ni, NiCr and SS304. eATRPs are performed both in divided and undivided electrochemical cells operating under either potentiostatic or galvanostatic mode. The reaction is fast, reaching high conversions in ≈4 h, and yields polymers with dispersity <1.2 and molecular weights close to the theoretical values. Most importantly, eATRP in a highly simplified setup (undivided cell under galvanostatic mode) with inexpensive nonnoble metals, such as NiCr and SS304, as cathode is well‐controlled. Additionally, these electrodes neither release harmful ions in solution nor react directly with the C X chain end and can be reused several times. It is demonstrated that Pt can be replaced with cheaper, and more readily available materials without negatively affecting eATRP performance.