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排序方式: 共有200条查询结果,搜索用时 15 毫秒
91.
Blaauw M. Ridikas D. Baytelesov S. Salas P. S. Bedregal Chakrova Y. Eun-Ha Cho Dahalan R. Fortunato A. H. Jacimovic R. Kling A. Muñoz L. Mohamed N. M. A. Párkányi D. Singh T. Van Dong Duong 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):409-418
Journal of Radioanalytical and Nuclear Chemistry - Molybdenum-99 is one of the most important radionuclides for medical diagnostics. In 2015, the International Atomic Energy Agency organized a... 相似文献
92.
Emanuel Carlos Prof. Rodrigo Martins Prof. Elvira Fortunato Prof. Rita Branquinho 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(42):9099-9125
Solution combustion synthesis (SCS) has been widely used to produce simple and complex oxides with a desired morphology (size and shape). SCS is valuable due to low cost, simplicity and energy efficient synthesis. To guarantee the best molecular-level mixing of reactants in an aqueous or solvent-based solution some parameters need to be controlled, such as fuel type, metal cations precursors, stoichiometry ratio (φ), pH effect, atmosphere and initiation type. These determine the final properties of the oxide materials, providing the potential to reach different morphologies, which are essential for their final applications. This Review article focuses on the crucial parameters in SCS and how these affect the overall materials properties from nanostructures to thin films. To finalize, special attention is given to the application of SCS to form metal oxide thin films at low temperature and their application in thin film transistors (TFTs). 相似文献
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Fine structure due to photothermal processes has been studied in the photoconductivity spectrum Si: S. For three levels (transitions of neutral donors with binding energies 109.5, 187.2 and 318.4 meV) excited states up to and including 4 p± are observed with linewidths limited by system resolution (? 0.2 meV). A new level is also tentatively identified with binding energy 0.155 eV. Resonance structure is observed in the continuum spectra of the two deepest levels due to excited state phonon replicas. The effect of electric fields up to 2 kV cm-1 is reported: the threshold shifts to lower energies, and highly excited states disappear, and a new line is observed. 相似文献
96.
Li Xinyue Fortunato Marco Cardinale Anna Maria Sarapulova Angelina Njel Christian Dsoke Sonia 《Journal of Solid State Electrochemistry》2022,26(1):49-61
Journal of Solid State Electrochemistry - Nickel aluminum layered double hydroxide (NiAl LDH) with nitrate in its interlayer is investigated as a negative electrode material for lithium-ion... 相似文献
97.
Antonio Guerriero Michele D'Ambrosio Vincenzo Cuomo Fortunato Vanzanella Francesco Pietra 《Helvetica chimica acta》1989,72(3):438-446
Further investigation of global extracts from cultures of the marine deuteromycete Dendryphiella salina leads to the isolation of three novel trinor-eremophilanes esterified by branched C9-carboxylic acids, dendryphiellin B (= (+)-(1R*,2S*,7R*,8aR*)-1,2,6,7,8,8a-hexahydro-7-hydroxy-1,8a-dimethyl-6-oxonaphthalen-2-yl (6R*, 2E, 4E)-6-hydroxy-6-methylocta-2,4-dienoate; (+)- 2 ), dendryphiellin C (=(+)-(1R*, 2S*, 7R*, 8aR*)-1,2,6,7,8,8a-hexa-hydro-7-hydroxy-1,8a-dimethyl-6-oxonaphthalen-2-yl (6S, 2E, 4E)-6-methylocta-2,4-dienoate; (+)- 3 )), and dendryphiellin D (=(+)-(1R*, 2S*, 7R*, 8aR*)-1,2,6,7(8,8a-hexahydro-7-hydroxy-1,8a-dimethyl-6-oxonaphthalen-2-yl (6R*,2E,4E)-6-(hydroxymethyl)octa-2,4-dienoate; (+)- 4 ). An intact eremophilane, dendryphiellin E ( 5 ), and its ethanolysis product dendryphiellin F whose absolute configuration is represented by structural formula (+)- 6 are also isolated from the above extracts. Dendryphiellin E exists as an open form 5a in equilibrium with a closed form 5b . A similar equilibrium exists between the open form 8a and the closed form 8b of a non-esterified eremophilane, dendryphiellin G ( 8 ), which is isolated too from the above extracts and proves structurally related to the cyclic portion of 5 . Finally, the free, branched C9-carboxylic acids dendryphiellic acid A ((+)- 9 ) and B ((+)- 10 ) which correspond to side chains of the above esterified terpenes are also isolated from the above extracts. 相似文献
98.
Werickson Fortunato de Carvalho Rocha 《Microchemical Journal》2010,96(1):21-40
Near infrared spectroscopic and multivariate statistical control charts based on the net analyte signal (NAS) were applied to the polymorphic characterization of Piroxicam samples. Three different polymorphic forms (I, II and III) were studied, using X-ray powder diffraction (XRPD) and scanning electron microscopy as reference techniques. Samples containing form I were considered inside the quality specifications and forms II and III were impurities. Three control charts were developed: the NAS chart that corresponds to the analyte of interest (polymorphic form I), the interference chart that corresponds to the contribution of other compounds in the sample and the residual chart that corresponds to nonsystematic variation. From the limits estimated for each chart using samples inside the quality specifications, it was possible to identify samples that did not present polymorphic form I. The use of multivariate control charts provides a rapid evaluation of purity and the polymorphic composition of pharmaceutical formulations based on Piroxicam. 相似文献
99.
Fortunato M. Giustiniani A. Petrone G. Spagnuolo G. Vitelli M. 《Industrial Electronics, IEEE Transactions on》2008,55(7):2684-2693
In this paper, the design of the one-cycle controller of a single-stage inverter for photovoltaic applications is carried out by means of a multiobjective strategy to optimize inverter performance at both high and low insolation levels. Design constraints that account for different weather conditions are adopted. The optimization algorithm also provides useful information concerning the system sensitivity with respect to each of the controller parameters. This allows the design of a maximum power point tracking perturb and observe controller that significantly improves inverter performance. Experimental measurements confirm the predictions of theoretical and simulation results. 相似文献
100.
Andrea GeltrudeKais Al Naimee Stefano EuzzorRiccardo Meucci Fortunato Tito Arecchi Binoy Krishna Goswami 《Communications in Nonlinear Science & Numerical Simulation》2012,17(7):3031-3039
With a modulated CO2 laser as a standard model of periodically driven multistable systems, we experimentally demonstrate that a small-amplitude optoelectronic feedback perturbation can efficiently transform a bursting chaotic system to a nonchaotic one. Numerical simulations are in excellent agreement with the experimental results. The control has also been equally effective in the case of a driven FitzHugh-Nagumo model of Neuroscience. 相似文献