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91.
G. Benassi N. Zambelli M. Villani D. Calestani M. Pavesi A. Zappettini L. Zanotti C. Paorici 《Crystal Research and Technology》2013,48(4):245-250
Several materials are under investigations for flat panel x‐ray detector applications. Among them, PbO shows interesting properties, i.e. high sensitivity, large stopping power and high resistivity at room temperature. However, the exploitation of PbO is limited by the difficulty to obtain good quality films constituted by a single phase. In this paper, we describe a new approach for the vapour phase growth of orthorhombic PbO films. The grown layers show a single phase, good crystallinity, and preferential orientation along the c axis. Optical characterization evidenced the presence of a broad defect band. Gold contacted films showed very high electrical resistivity and appreciable response to X‐ray radiation. 相似文献
92.
Laura Llauger Costanza Bergami Olaf D. Kinzel Samuele Lillini Giovanna Pescatore Caterina Torrisi Philip Jones 《Tetrahedron letters》2009,50(2):172-1385
Functionalized fused heteroaryl pyrazinones were built up through a novel DBU-catalyzed intramolecular hydroamination reaction of aryl(prop-2-yn-1-yl)-1H-heteroaryl-2-carboxamides. The nucleophilic addition afforded three isomers; two with an exo-cyclic double bond [cis (Z), trans (E)], and a third one with an endo-cyclic double bond. After the carboxamide deprotection, isomerization of the mixture under acidic conditions resulted in a unique isomer. 相似文献
93.
Costanza Conti Mariantonia Cotronei Tomas Sauer 《Journal of Approximation Theory》2010,162(3):559-575
We extend our previous work on interpolatory vector subdivision schemes to the multivariate case. As in the univariate case we show that the diagonal and off-diagonal elements of such a scheme have a significantly different structure and that under certain circumstances symmetry of the mask can increase the polynomial reproduction power of the subdivision scheme. Moreover, we briefly point out how tensor product constructions for vector subdivision schemes can be obtained. 相似文献
94.
In this work, we assess three different methods for the extraction of pectin from waste orange peels, using water as extracting solvent. “Hot-water”, Rapid Solid Liquid Dynamic (RSLD) and microwave-assisted extractions have been compared and evaluated in terms of amount and quality of extracted pectin, as well as embodied energy. This analysis provides useful guidelines for pectin production from food waste according to green procedures, enabling the identification of acidic “hot-water” as the most sustainable extraction route. 相似文献
95.
Evidence for Degradation of the Chrome Yellows in Van Gogh’s Sunflowers: A Study Using Noninvasive In Situ Methods and Synchrotron‐Radiation‐Based X‐ray Techniques 下载免费PDF全文
Dr. Letizia Monico Prof. Koen Janssens Dr. Ella Hendriks Frederik Vanmeert Dr. Geert Van der Snickt Dr. Marine Cotte Dr. Gerald Falkenberg Prof. Brunetto Giovanni Brunetti Dr. Costanza Miliani 《Angewandte Chemie (International ed. in English)》2015,54(47):13923-13927
This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh’s Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron‐radiation‐based X‐ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur‐rich PbCr1?xSxO4 (x≈0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., CrIII compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future. 相似文献
96.
To estimate the thermochemical properties, bond dissociation energies and atomization energies of sulfur organic derivatives, the complete basis set (CBS) method was employed at the lower computational level (CBS‐4) owing to the large molecular size of a number of the molecules chosen. By comparison with experimental values, calculated values of thermochemical properties are subject to error, which increases in line with the increase in molecular complexity. The main source of error affecting the calculated enthalpy of formation stems from the difference between the energy of the molecule and that of the single atoms: the greater the size of the molecule, the greater the accumulation of error. By acting on the empirical correction to the CBS energy and minimizing the error due to the contribution of the single atoms to the dissociation energy a parameter di for each atom i is obtained. Application of these corrections does not greatly affect the heats of formation of the small molecules included in test sets employed for previous comparisons of calculated and experimental values, while there is a great improvement in the case of large molecules, for example, diphenyl disulfide. The mean absolute deviation turns out to be 2.52, which is greater than that obtained in recent reexaminations of model chemistry methods including the G3 and G3(MP3) approaches. The improvement in the results calculated for large molecules, whose heats of formation are calculated with large errors at the CBS‐4 level, in comparison also with the CBS‐4M version, justify our approach. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 1405–1418, 2000 相似文献
97.
Costanza Vanni Anne Bodlenner Marco Marradi Jrmy P. Schneider Maria de los Angeles Ramirez Sergio Moya Andrea Goti Francesca Cardona Philippe Compain Camilla Matassini 《Molecules (Basel, Switzerland)》2021,26(19)
Among carbohydrate-processing enzymes, Jack bean α-mannosidase (JBα-man) is the glycosidase with the best responsiveness to the multivalent presentation of iminosugar inhitopes. We report, in this work, the preparation of water dispersible gold nanoparticles simultaneously coated with the iminosugar deoxynojirimycin (DNJ) inhitope and simple monosaccharides (β-d-gluco- or α-d-mannosides). The display of DNJ at the gold surface has been modulated (i) by using an amphiphilic linker longer than the aliphatic chain used for the monosaccharides and (ii) by presenting the inhitope, not only in monomeric form, but also in a trimeric fashion through combination of a dendron approach with glyconanotechnology. The latter strategy resulted in a strong enhancement of the inhibitory activity towards JBα-man, with a Ki in the nanomolar range (Ki = 84 nM), i.e., more than three orders of magnitude higher than the monovalent reference compound. 相似文献
98.
Veronika I. Komlyagina Nikolay F. Romashev Vasily V. Kokovkin Artem L. Gushchin Enrico Benassi Maxim N. Sokolov Pavel A. Abramov 《Molecules (Basel, Switzerland)》2022,27(20)
Self-assembly of (Bu4N)4[β-Mo8O26], AgNO3, and 2-bis[(2,6-diisopropylphenyl)-imino]acenaphthene (dpp-bian) in DMF solution resulted in the (Bu4N)2[β-{Ag(dpp-bian)}2Mo8O26] (1) complex. The complex was characterized by single crystal X-ray diffraction (SCXRD), X-ray powder diffraction (XRPD), diffuse reflectance (DR), infrared spectroscopy (IR), and elemental analysis. Comprehensive SCXRD studies of the crystal structure show the presence of Ag+ in an uncommon coordination environment without a clear preference for Ag-N over Ag-O bonding. Quantum chemical calculations were performed to qualify the nature of the Ag-N/Ag-O interactions and to assign the electronic transitions observed in the UV–Vis absorption spectra. The electrochemical behavior of the complex combines POM and redox ligand signatures. Complex 1 demonstrates catalytic activity in the electrochemical reduction of CO2. 相似文献
99.
Costanza Conti Luca Gemignani Lucia Romani 《Advances in Computational Mathematics》2013,39(2):395-424
This paper describes an algebraic construction of bivariate interpolatory subdivision masks induced by three-directional box spline subdivision schemes. Specifically, given a three-directional box spline, we address the problem of defining a corresponding interpolatory subdivision scheme by constructing an appropriate correction mask to convolve with the three-directional box spline mask. The proposed approach is based on the analysis of certain polynomial identities in two variables and leads to interesting new interpolatory bivariate subdivision schemes. 相似文献
100.
N-benzyl-tert-butyl nitroxide derivatives substituted at the aromatic ring form host-guest inclusion complexes with β-and γ-cyclodextrin. They were employed as probes to assess substituent effects on the geometry of the complex and on the kinetics of this complexation by combining EPR and (1)H NMR data. 相似文献