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161.
162.
Benedetti TM Bazito FF Ponzio EA Torresi RM 《Langmuir : the ACS journal of surfaces and colloids》2008,24(7):3602-3610
Thin films of MnO(2) nanoparticles were grown using the layer-by-layer method with poly(diallyldimetylammonium) as the intercalated layer. The film growth was followed by UV-vis, electrochemical quartz crystal microbalance (EQCM), and atomic force microscopy. Linear growth due to electrostatic immobilization of layers was observed up to 30 bilayers, but electrical connectivity was maintained only for 12 MnO(2)/PPDA bilayers. The electrochemical characterization of this film in 1-butyl-2,3-dimethyl-imidazolium (BMMI) bis(trifluoromethanesulfonyl)imide (TFSI) (BMMITFSI) with and without addition of a lithium salt indicated a higher electrochemical response of the nanostructured electrode in the lithium-containing electrolyte. On the basis of EQCM experiments, it was possible to confirm that the charge compensation process is achieved mainly by the TFSI anion at short times (<2 s) and by BMMI and lithium cations at longer times. The fact that large ions like TFSI and BMMI participate in the electroneutrality is attributed to the redox reaction that occurs at the superficial sites and to the high concentration of these species compared to that of lithium cations. 相似文献
163.
This article considers the non-linear mixed 0–1 optimization problems that appear in topology optimization of load carrying
structures. The main objective is to present a Generalized Benders’ Decomposition (GBD) method for solving single and multiple
load minimum compliance (maximum stiffness) problems with discrete design variables to global optimality. We present the theoretical
aspects of the method, including a proof of finite convergence and conditions for obtaining global optimal solutions. The
method is also linked to, and compared with, an Outer-Approximation approach and a mixed 0–1 semi definite programming formulation
of the considered problem. Several ways to accelerate the method are suggested and an implementation is described. Finally,
a set of truss topology optimization problems are numerically solved to global optimality. 相似文献
164.
Denise Tofanello Gimenes Wallans Torres Pio dos Santos Rodrigo Alejandro Abarza Munoz Eduardo Mathias Richter 《Electrochemistry communications》2010,12(2):216-218
In this work, we describe for the first time the use of the internal standard method in flow injection analysis (FIA) with amperometric detection. The method is based on the application of sequential potential pulses to the working electrode in an electrochemical flow cell. The sequence of potential pulses is selected in such a way that the analyte and internal standard compound are detected and monitored individually and independently at the same working electrode. This approach compensates for random errors associated with variations of flow rate, injection volume, ionic strength difference between standards and samples, and accidental insertion or formation of air bubbles in the carrier stream. In addition, this method can overcome the major drawback of amperometric detection using solid electrodes, which is gradual electrode passivation. To illustrate the potential of this method, the flow-injection amperometric detection of uric acid using [Fe(CN)6]3? as an internal standard (IS) is presented as an example. 相似文献
165.
Eduardo Soares Rodrigues Paulo Murilo Castro de Oliveira 《Journal of statistical physics》1994,74(5-6):1265-1272
We consider a nearest-neighbor-interaction ±J Ising spin glass in a square lattice. Inspired by natural evolution, we design a dynamic rule that includesselection, randomness, andmultibranch exploration. Following this rule, we succeed in walking along the space of states between local energy maxima and minima alternately. During the walk, we store various information about the spin states corresponding to these minima and maxima for later statistical analysis. In particular, we plot a histogram displaying how many times each minimum (or maximum) energy is visited as a function of the corresponding density value. Through finite-size scaling analysis, we conclude that a nonvanishing fraction of bonds remains unsatisfied (satisfied) at these energy minimum (maximum) states in the thermodynamic limit. This fraction measures the degree of unavoidable frustration of the system. Also in this limit, the width of these histograms vanishes, meaning that almost all metastable states occur at the same energy density value, with no dispersion. 相似文献
166.
Santiago Pedro H. O. Fujimori Mahmi Chagas Marcio A. S. França Eduardo L. Honorio-França Adenilda C. Gatto Claudia C. 《Structural chemistry》2020,31(1):171-180
Structural Chemistry - Two novel Cu(I) complexes with the 2-acetylpyridine-N(4)-phenyl semicarbazone (HL) ligand, [CuCl (HL)(PPh3)]∙CH3CN (1) and [CuBr (HL)(PPh3)] (2), were investigated by... 相似文献
167.
168.
María Constanza Luciardi María Amparo Blzquez María Rosa Alberto Elena Cartagena Mario Eduardo Arena 《Molecules (Basel, Switzerland)》2021,26(10)
The chemical composition of three Citrus limon oils: lemon essential oil (LEO), lemon terpenes (LT) and lemon essence (LE), and their influence in the virulence factors production and motility (swarming and swimming) of two Pseudomonas aeruginosa strains (ATCC 27853 and a multidrug-resistant HT5) were investigated. The main compound, limonene, was also tested in biological assays. Eighty-four compounds, accounting for a relative peak area of 99.23%, 98.58% and 99.64%, were identified by GC/MS. Limonene (59–60%), γ-terpinene (10–11%) and β-pinene (7–15%) were the main compounds. All lemon oils inhibited specific biofilm production and bacterial metabolic activities into biofilm in a dose-dependent manner (20–65%, in the range of 0.1–4 mg mL−1) of both strains. Besides, all samples inhibited about 50% of the elastase activity at 0.1 mg mL−1. Pyocyanin biosynthesis decreases until 64% (0.1–4 mg mL−1) for both strains. Swarming motility of P. aeruginosa ATCC 27853 was completely inhibited by 2 mg mL−1 of lemon oils. Furthermore, a decrease (29–55%, 0.1–4 mg mL−1) in the synthesis of Quorum sensing (QS) signals was observed. The oils showed higher biological activities than limonene. Hence, their ability to control the biofilm of P. aeruginosa and reduce the production of virulence factors regulated by QS makes lemon oils good candidates to be applied as preservatives in the food processing industry. 相似文献
169.
170.