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81.
de Araújo Moisés A. Lucas Francisco W. S. Mascaro Lucia H. 《Journal of Solid State Electrochemistry》2020,24(2):389-399
Journal of Solid State Electrochemistry - The present work outlines a simple and novel approach to obtain nanostructured and heterostructured SnS/Sb2S3 thin films. This material showed enhanced... 相似文献
82.
Enrico Luchinat Letizia Barbieri Matteo Cremonini Alessio Nocentini Claudiu T. Supuran Lucia Banci 《Angewandte Chemie (International ed. in English)》2020,59(16):6535-6539
Structure‐based drug development is often hampered by the lack of in vivo activity of promising compounds screened in vitro, due to low membrane permeability or poor intracellular binding selectivity. Herein, we show that ligand screening can be performed in living human cells by “intracellular protein‐observed” NMR spectroscopy, without requiring enzymatic activity measurements or other cellular assays. Quantitative binding information is obtained by fast, inexpensive 1H NMR experiments, providing intracellular dose‐ and time‐dependent ligand binding curves, from which kinetic and thermodynamic parameters linked to cell permeability and binding affinity and selectivity are obtained. The approach was applied to carbonic anhydrase and, in principle, can be extended to any NMR‐observable intracellular target. The results obtained are directly related to the potency of candidate drugs, that is, the required dose. The application of this approach at an early stage of the drug design pipeline could greatly increase the low success rate of modern drug development. 相似文献
83.
Lucia Bartella Leonardo Di Donna Anna Napoli Giovanni Sindona Fabio Mazzotti 《Journal of mass spectrometry : JMS》2020,55(9)
A fast methodology for the assay of parabens in drug and cosmetic preparations has been presented. The procedure developed is based on paper spray tandem mass spectrometry and isotope dilution approach. For each investigated paraben, the corresponding labeled standard has been used in order to improve the accuracy and reproducibility of the analyses. The MS experiments have been performed under MRM conditions, monitoring the transitions [M‐H]? → m/z 92 and [M‐H]? → m/z 98, respectively, for each analyte and the corresponding labeled internal standard. The quantitative assay has been performed using a calibration curve built from 2 to 15 mg/L. The method accuracy, in all case near 100%, was evaluated using fortified samples at two concentration levels, which are representative of the lower and the higher portion of calibration curve. The good values of LOQ, LOD, and reproducibility confirm the consistency of the developed approach. 相似文献
84.
Ana Barragn Ane Sarasola Lucia Vitali 《Angewandte Chemie (International ed. in English)》2020,59(36):15599-15602
Efficiency in charge‐transport is a fundamental but demanding prerequisite to allow better exploitation of molecular functionalities in organic electronics and energy‐conversion systems. Here, we report on a mechanism that enables a one‐dimensional conductance structure by connecting discrete molecular states at 2.1 eV through the pores of a metal–organic network on Cu(110). Two adjacent, periodic and isoenergetic contributions, namely a molecular resonance and the confined surface‐state, add‐up leading to anisotropic structures, as channels, observable in real‐space conductance images. The adsorption configurations of Br atoms, inorganic byproduct of the redox‐reacted 4,7‐dibromobenzo[c]‐1,2,5‐thiadiazole (2Br‐BTD) molecules on the copper surface, drive the confinement of the Cu surface state within the pores and critically control the channel continuity. Small displacements of the Br atoms change the local surface potential misaligning the energy levels. This work visualizes the effect of order‐disorder transitions caused by the movement of single atoms in the electronic properties of two‐dimensional organic networks. 相似文献
85.
Lucia Veltri Roberta Amuso Raffaella Mancuso Bartolo Gabriele 《Molecules (Basel, Switzerland)》2022,27(1)
In this short review, we highlight the advancements in the field of palladium-catalyzed carbon dioxide utilization for the synthesis of high value added organic molecules. The review is structured on the basis of the kind of substrate undergoing the Pd-catalyzed carboxylation process. Accordingly, after the introductory section, the main sections of the review will illustrate Pd-catalyzed carboxylation of olefinic substrates, acetylenic substrates, and other substrates (aryl halides and triflates). 相似文献
86.
Bramanti E D'Ulivo L Lomonte C Onor M Zamboni R Raspi G D'Ulivo A 《Analytica chimica acta》2006,579(1):38-46
A new procedure is proposed for the sampling and storage of hydrogen sulphide (H2S) and volatile thiols (methanethiol or methyl mercaptan, ethanethiol and propanethiol) for their determination by liquid chromatography. The sampling procedure is based on the trapping/pre-concentration of the analytes in alkaline aqueous solution containing an organic mercurial probe p-hydroxymercurybenzoate, HO-Hg-C6H4-COO− (PHMB), where they are derivatized to stable PHMB complexes based on mercury-sulfur covalent bonds. PHMB complexes are separated on a C18 reverse phase column, allowing their determination by liquid chromatography coupled with sequential non-selective UV-vis (DAD) and mercury specific (chemical vapor generation atomic fluorescence spectrometry, CVGAFS) on-line detectors. PHMB complexes, S(PHMB)2CH3S-PHMB, C2H5S-PHMB and C3H7S-PHMB, are stable alt least for 12 h at room temperature and for 3 months if stored frozen (−20 °C).The best analytical figures of merits in the optimized conditions were obtained by CVGAFS detection, with detection limits (LODc) of 9.7 μg L−1 for H2S, 13.7 μg L−1 for CH3SH, 17.7 μg L−1 for C2H5SH and 21.7 μg L−1 for C3H7SH in the trapping solution in form of RS-PHMB complexes, the relative standard deviation (R.S.D.) ranging between 1.0 and 1.5%, and a linear dynamic range (LDR) between 10 and 9700 μg L−1. Conventional UV absorbance detectors tuned at 254 nm can be employed as well with comparable R.S.D. and LDR, but with LODc one order of magnitude higher than AFS detector and lower specificity. The sampling procedure followed by LC-DAD-CVGAFS analysis has been validated, as example, for H2S determination by a certified gas permeation tube as a source of 3.071 ± 0.154 μg min−1 of H2S, giving a recovery of 99.8 ± 7% and it has been applied to the determination of sulfur compounds in real gas samples (biogas and the air of a plant for fractional distillation of crude oil). 相似文献
87.
A. BallaG. Bencivenni M. CapodiferroS. Cerioni P. CiambroneE. De Lucia G. De RobertisA. Di Domenico D. Domenici J. DongG. Felici M. GattaM. Jacewicz N. LacalamitaS. Lauciani R. LiuzziF. Loddo M. MongelliM. Morello V. PateraA. Pelosi M. PistilliL. Quintieri A. RanieriM. Schioppa E. TshadadzeV. Valentino 《Nuclear Physics B - Proceedings Supplements》2011,215(1):76-78
88.
89.
Andrea Petrella Pinalysa Cosma M. Lucia Curri Sergio Rochira Angela Agostiano 《Journal of nanoparticle research》2011,13(12):6467-6481
Heterostructures formed of films of organic-capped ZnO and TiO2 nanocrystals (both with the size of ca. 6 nm) and photosynthetic pigments were prepared and characterized. The surface of
optically transparent electrodes (Indium Tin Oxide) was modified with nanocrystals and prepared by colloidal synthetic routes.
The nanostructured electrodes were sensitized by a mixture of chlorophyll a and carotenoids. The characterization of the hybrid
structures, carried out by means of steady-state optical measurements, demonstrated such class of dyes able to extend the
photoresponse of the large band-gap semiconductors. The charge-transfer processes between the components of the heterojunction
were investigated, and photoelectrochemical measurements taken on the sensitized ZnO and TiO2 nanocrystals electrodes elucidated the photoactivity of the heterojunctions as a function of the dyes and of the red–ox mediator
used in solution. The effect of methyl viologen as different red–ox mediator was also evaluated in order to show its effect
on the heterojunction photoactivity. The overall results contributed to describe the photoelectrochemical potential of the
investigated heterojunctions, highlighting a higher response of the dye-sensitized ZnO nanocrystals, and then provided the
TiO2-modified counterparts. 相似文献
90.
Lucia Gionfriddo 《Discrete Mathematics》2010,310(22):3067-620
A dodecagon quadrangle is the graph consisting of two cycles: a 12-cycle (x1,x2,…,x12) and a 4-cycle (x1,x4,x7,x10). A dodecagon quadrangle system of order n and index ρ [ DQS] is a pair (X,H), where X is a finite set of n vertices and H is a collection of edge disjoint dodecagon quadrangles (called blocks) which partitions the edge set of ρKn, with vertex set X. A dodecagon quadrangle system of order n is said to be perfect [PDQS] if the collection of 4-cycles contained in the dodecagon quadrangles form a 4-cycle system of order n and index μ. In this paper we determine completely the spectrum of DQSs of index one and of PDQSs with the inside 4-cycle system of index one. 相似文献