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991.
Diana Caponetti 《Rendiconti del Circolo Matematico di Palermo》1991,40(2):241-250
LetE′ be the separable dual of a Banach spaceE. LetK be the class of all non-empty convex, weak*-compact subsets ofE′. In this paper we prove that Edgar’s inequality, given in [2], extends to
adapted sequences ofK-valued random variables. 相似文献
992.
Dorel Crişan Nicolae Drăgan Maria Crişan Adelina Ianculescu Ligia Todan Jacques C. Védrine Diana Filkova Margarita Gabrovska Rumeana Edreva Kardjieva 《Comptes Rendus Chimie》2018,21(3-4):232-246
The aim of the present work was to prepare a binary MO–Nd2O3 system by the sol–gel method and to characterise a series of mixed oxides belonging to the binary MO–Nd2O3 system (M = alkaline earth metal = Mg, Ca, Sr) to obtain suitable materials with catalytic properties. The molar ratio between the two oxides was MO/Nd2O3 = 95/5. Different precursors as alkaline earth metal oxide source (MO), various starting solution compositions expressed in various molar ratios between reactants and different synthesis parameters (pH, temperature and time of reaction) have been used. The structural study by X-ray diffraction analysis was accomplished based on the X-ray 5.0 program, which has established the presence of the mixtures of crystalline polyphases. The lattice constants, the average size of the crystallites, the average lattice strains and the mass of unit cell variation have been calculated. The program also allowed the calculus of the anisotropy factor, which can give the image of the structural disorder. The surface defects are a consequence of structural changes inside of the crystalline lattice of the solid solutions and are quite important for catalytic properties. Some catalytic activity measurements have established the potential of the prepared sol–gel mixed oxides to be used in the oxidative dehydrogenation process of light alkanes (C1C4). Sample 3SrNd was shown to present the best catalytic activity and selectivity in olefins in propane conversion () compared with 4Ca-Nd and 1Mg-Nd samples, which was interpreted as due to a better solid solution formation of Nd3+ in SrO, favoured by the close ionic radius of Sr2+ and Nd3+, as well as by the high basicity of Sr and the presence of a greater number of point defects. 相似文献
993.
Numerical self-consistent field (SCF) calculations in density functional theory (DFT) and the local spin-density approximation (LSDA) were performed for the light atoms H, Li, B, C, N, O and F, in order to investigate the effect of the self-interaction correction (SIC) on the isotropic (or contact) hyperfine parameter AISO. In contrast to the findings for certain 3d-metals and compounds, results for light-atom SI-corrected AISO present no improvement over the LSDA values. We show that relatively modest changes to the correlation potential can lead to significant improvement of densities near the nucleus and the related AISO, suggesting a direction for future improvements in DFT functionals. 相似文献
994.
Yiran Huang Hong-Jun Cho Nilantha Bandara Liang Sun Diana Tran Buck E. Rogers Liviu M. Mirica 《Chemical science》2020,11(30):7789
While Alzheimer''s Disease (AD) is the most common neurodegenerative disease, there is still a dearth of efficient therapeutic and diagnostic agents for this disorder. Reported herein are a series of new multifunctional compounds (MFCs) with appreciable affinity for amyloid aggregates that can be potentially used for both the modulation of Aβ aggregation and its toxicity, as well as positron emission tomography (PET) imaging of Aβ aggregates. Firstly, among the six compounds tested HYR-16 is shown to be capable to reroute the toxic Cu-mediated Aβ oligomerization into the formation of less toxic amyloid fibrils. In addition, HYR-16 can also alleviate the formation of reactive oxygen species (ROS) caused by Cu2+ ions through Fenton-like reactions. Secondly, these MFCs can be easily converted to PET imaging agents by pre-chelation with the 64Cu radioisotope, and the Cu complexes of HYR-4 and HYR-17 exhibit good fluorescent staining and radiolabeling of amyloid plaques both in vitro and ex vivo. Importantly, the 64Cu-labeled HYR-17 is shown to have a significant brain uptake of up to 0.99 ± 0.04 %ID per g. Overall, by evaluating the various properties of these MFCs valuable structure–activity relationships were obtained that should aid the design of improved therapeutic and diagnostic agents for AD.A series of multifunctional compounds and their 64Cu complexes exhibit good affinity for Aβ aggregates and can also control Aβ toxicity. 相似文献
995.
Diana Martin 《Talanta》2007,71(2):751-757
Analysis of polycyclic aromatic hydrocarbons (PAHs) standards in model systems was carried out by solid-phase microextraction (SPME) coupled to a direct extraction device (DED) and subsequent gas chromatography/mass spectrometry (GC/MS). PAHs standard was added to gelatine systems at different concentrations. Extraction process was carried out by SPME-DED at 25 °C for 60 min. Polydimethylsiloxane 100 μm (PDMS 100 μm), divinylbenzene/polydimethylsiloxane 65 μm (DVB/PDMS 65 μm) and polyacrilate 85 μm (PA 85 μm) SPME fibres were tested. SPME-DED satisfactorily extracted PAHs with a molecular weight (MW) lower than 206 from the gelatine system. All fibres showed a good reproducibility (residual standard deviation (RSD) between 5.24% and 18.25%), linearity (regression coefficients between 0.8959 and 0.9983) and limit of detection (LOD) (between 0.008 and 0.138 ng mL−1). Presence of PAHs in different smoked meat products was also tested by SPME-DED. Different low MW PAHs were satisfactorily detected from all the foodstuffs studied. SPME-DED appears as a rapid, non-destructive technique for primary screening of low MW PAHs in solid matrixes. 相似文献
996.
Diana L.D. Lima 《Talanta》2007,72(4):1404-1409
Operational parameters like migration time, temperature, voltage, composition of background electrolyte and content of organic modifier were optimized in CZE for the determination of lignin-like phenolic compounds.The applied background electrolyte buffer consisted of a Na2B4O7, KH2PO4 aqueous solution, pH 9.15 using acetonitrile as organic modifier with UV-detection. Compounds, such as acetosyringone, acetovanillone, syringealdehyde, p-hydroxyacetophenone, vanillin, syringic acid, ferulic acid, p-hydroxybenzaldehyde, p-coumaric acid, vanillic acid and p-hydroxybenzoic acid were applied as reference compounds.The quality and quantity of different phenolic compounds obtained upon alkaline CuO oxidation of a commercial humic acid were determined with CZE using ethylvanillin as internal standard.The optimized CZE revealed has being an appropriate method since it is quick, sensitive and quantitative and does not require a time-consuming sample preparation. 相似文献
997.
Cui X Thomas A Montgomery D Gu C Morrison RA White RE Cheng KC 《Combinatorial chemistry & high throughput screening》2005,8(4):341-346
Recent studies have suggested that both constitutive androstane receptor (CAR) and pregnane X-receptor (PXR) are involved in the induction of rat liver microsomal cytochrome P-450 (CYP) 2B and 3A through a mechanism called cross-talk. In this study we intend to determine if a PXR-reporter gene assay could be used for the prediction of CYP3A and/or CYP2B induction in rats. The induction of rat CYP2B and CYP3A by nineteen structurally diverse compounds was evaluated by using rat precision-cut liver slices and a rat PXR reporter-gene system. Induction of CYP2B and CYP3A mRNAs in rat liver slices was quantified by real-time polymerase chain reaction. Rat PXR activation was measured by induction of luciferase activity in rat PXR reporter-gene system. Linear regression analysis of the fold of induction of mRNA in liver slices and the fold of luciferase activity in rat PXR reporter-gene system shows that a reasonable correlation (r2 = 0.6) exists between the CYP3A induction and the rat PXR activation. A much lower correlation was observed between CYP2B induction and the rat PXR activation (r2 = 0.1). The results from this study suggest that the PXR may play a major role in the induction of rat CYP3A, but not CYP2B. Therefore, the PXR-reporter gene assay may be useful in a high-throughput screening to predict CYP3A induction in rats. 相似文献
998.
Diana Ciuhandu Christine Degel Johanna Schreiber und G. Ciuhandu 《Fresenius' Journal of Analytical Chemistry》1978,292(3):238-239
Ohne Zusammenfassung
Separation and determination of 1-aminoanthraquinone- and 1-amino-4-bromoanthraquinonesulphonic acid by paper chromatography相似文献
999.
Mauro Maestri Diana Sandrini Vincenzo Balzani Alex von Zelewsky Philippe Jolliet 《Helvetica chimica acta》1988,71(1):134-139
The absorption and emission spectra, emission lifetimes, luminescence quantum yields, and electrochemical behavior of the complexes Pd(Phpy)2, Pd(Thpy)2, and Pd(bhq)2 (Phpy?, Thpy?, and bhq?, and bhq? are the deprotonated forms of 2-phenylpyridine, 2-(2-thienyl)pyridine, and benzo[h] quinoline, respectively) have been studied, and the results obtained have been compared with those available for Pt(II) and Pt(IV) complexes containing the same ligands. The intense ligand-centered absorption bands below 340 nm are strongly perturbed by matalation, and the absorption features in the 340–450-nm region are likely to include contributions from formally metal-to-ligand charge-transfer transitions. The structured luminescence spectra observed at 77 K (lifetimes are 0.48, 0.28 and 2.6 ms for Pd(Phpy)2, Pd(Thpy)2, and Pd(bhq)2, respectively) have been assigned to transitions having mainly ligand-centered character, with an increasing metal-to-ligand charge-transfer contribution in going from Pd(bhq)2 to Pd(Phpy)2 and to Pd(Thpy)2. The complexes Pd(phpy)2 and Pd(thpy)2 show two reversible one-electron reduction waves, whereas reduction of Pd(bhq)2 is irreversible, as is the oxidation of the three complexes. 相似文献
1000.
Peter D. J. Grootenhuis Diana C. Roe Peter A. Kollman Irwin D. Kuntz 《Journal of computer-aided molecular design》1994,8(6):731-750
Summary For the first time a general shape-search docking algorithm (DOCK) has been applied to the minor and major grooves of A-, B- and Z-type DNA dodecamers and to an intercalation site in a B-DNA-type hexamer. Both experimentally and theoretically derived geometries for the various DNA fragments were used. The DOCK searches were carried out on a subset of the Cambridge Crystallographic Database, consisting of almost 10 000 molecules. One of the molecules that scored best in terms of the DOCK algorithm was CC-1065, a potent antitumor agent known to (covalently) bind the AT-rich parts of the minor groove of B-DNA. Several known DNA-binding agents also scored highly. Molecules with shapes complementary to A-, B- and Z-type DNA were indicated by DOCK. In addition, compounds were extracted from the database that might be selective for the GC-rich regions of the minor groove of B-DNA. Many of the compounds in the present study may serve as a starting point for further molecular design of novel DNA-binding ligands. 相似文献