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211.
The action of polyphosphoric acid on some N-phenylhydrazidoyl chlorides has been studied. Indazoles, di-hydrophthalazines or Hoffmann-Martius rearranged products were obtained depending on the particular substrate employed. 相似文献
212.
The assembling of [Mn(5-MeOsalen)(H2O)]+ and [(Tp)Fe(CN)3]- affords the one-dimensional zigzag chain [(Tp)Fe(CN)3Mn(5-MeOsalen).2CH3OH]n [1; Tp- = hydrotris(pyrazolyl)borate and 5-MeOsalen2- = N,N'-ethylenebis(5-methoxysalicylideneiminate)]. The corroborated experimental and ab initio data indicate ferromagnetic Fe(III)-Mn(III) couplings and D < 0 anisotropy on Mn(III). The field-induced metamagnetic behavior is due to interchain effects. 相似文献
213.
Marilena Mitrouli 《Numerical Algorithms》2011,57(2):169-186
In this paper we show that every matrix in the class of Sylvester Hadamard matrices of order 2
k
under H-equivalence can have full row and column sign spectrum, meaning that tabulating the numbers of sign interchanges
along any row (or column) gives all integers 0,1,...,2
k
− 1 in some order. The construction and properties of Yates Hadamard matrices are presented and is established their equivalence
with the Sylvester Hadamard matrices of the same order. Finally, is proved that every normalized Hadamard matrix has full
column or row sign spectrum if and only if is H-equivalent to a Sylvester Hadamard matrix. This provides us with an efficient
criterion identifying the equivalence of Sylvester Hadamard matrices. 相似文献
214.
Violeta Purcar Dan Donescu Cristian Petcu Marilena Vasilescu 《Journal of Dispersion Science and Technology》2013,34(9):1233-1239
We synthesized hybrid materials by sol-gel process, using: methyltriethoxysilane, tetraetylorthosilicate and vinyltriethoxysilane, in the presence of Rhodamine 6G. It was synthesized as well organic-inorganic hybrids with addition of tetraisopropyl orthotitanate and maleic anhydride UV-VIS spectra of dye show two absorption peaks at 499 nm (dimer) and 530 nm (monomer). Evaluating FTIR spectra of hybrid films, it was observed a band at 1077 cm?1, characteristic of the asymmetric Si-O-Si stretching vibration in oligomer. Fluorescence spectra show that tetraisopropyl orthotitanate presence in the composites modifies the nature of the inorganic matrix and affects the interaction with the added dye. 相似文献
215.
Antonio Junior Lepedda Gabriele Nieddu Silvia Rocchiccioli Pietro Fresu Pierina De Muro Marilena Formato 《Electrophoresis》2013,34(22-23):3227-3233
Bikunin is a plasma proteinase inhibitor often associated with inflammatory conditions. It has a half‐life of few minutes and it is rapidly excreted into urine as urinary trypsin inhibitor (UTI). UTI levels are usually low in healthy individuals but they can increase up to tenfold in both acute and chronic inflammatory diseases. This article describes a sensitive method for both direct UTI quantitation and structural characterization. UTI purification was performed by anion exchange micro‐chromatography followed by SDS‐PAGE. A calibration curve for protein quantitation was set up by using a purified UTI fraction. UTI identification and structural characterization was performed by Nano‐LC‐MS/MS analysis. The method was applied on urine samples from 9 patients with type 1 diabetes, 11 patients with type 2 diabetes, and 28 healthy controls, matched for age and sex with patients, evidencing higher UTI levels in both groups of patients with respect to controls (p < 0.001 and p = 0.001, respectively). Spearman's correlation tests highlighted no association between UTI levels and age in each group tested. Owing to the elevated sensitivity and specificity, the described method allows UTI quantitation from very low quantities of specimen. Furthermore, as UTI concentration is normalized for creatinine level, the analysis could be also performed on randomly collected urine samples. Finally, MS/MS analysis prospects the possibility of characterizing PTM sites potentially able to affect UTI localization, function, and pathophysiological activity. Preliminary results suggest that UTI levels could represent a useful marker of chronic inflammatory condition in type 1 and 2 diabetes. 相似文献
216.
Elvira M. Bauer Daniele Cecchetti Ettore Guerriero Simone Quaranta Francesca Ripanti Paolo Postorino Pietro Tagliatesta Marilena Carbone 《Molecules (Basel, Switzerland)》2022,27(11)
Due to the increasing tattoo practicing in Eastern countries and general concern on tattoo ink composition and safety, the green tattoo inks Green Concentrate by Eternal, for European and “for Asia Market Only” were analyzed, under the premise that only the former falls under a composition regulation. A separation of the additives from the pigment was carried out by successive extraction in solvents of different polarities, i.e., water, acetone and dichloromethane. The solid residues were analyzed by IR and Raman spectroscopies, the liquid fractions by GC/mass spectrometry. The relative pigment load and element traces were also estimated. We found that the European and the Asian inks are based on the same pigment, PG7, restricted in Europe, though at different loads. They have a similar content of harmful impurities, such as Ni, As, Cd and Sb and both contain siloxanes, including harmful D4. Furthermore, they have different physical-chemical properties, the European ink being more hydrophilic, the Asian more hydrophobic. Additionally, the Asian ink contains harmful additives for the solubilization of hydrophobic matrices and by-products of the phthalocyanine synthesis. Teratogenic phthalates are present as well as chlorinated teratogenic and carcinogenic compounds usually associated to the laser treatment for removal purposes, to a larger extent in the European ink. The composition of the inks does not seem to reflect regulatory restrictions, where issued. 相似文献
217.