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381.
R. Miotto J.F. R. Cunha M.A. G. Soler A.C. Ferraz D.F. S. Petri 《Applied Surface Science》2006,253(4):1978-1982
In the search of new photoactive species that may be of use either in energy conversion or in photodynamic therapy, we studied the functionalization of silicon (1 0 0) with thionin using the glutaraldehyde coupling reaction. Surface properties were obtained by ellipsometric measurements, atomic force microscopy, and luminescence spectroscopy, which indicated the formation of a well organised monolayer in the silicon surface. In addition, the comparison of Raman spectroscopy data with first-principles pseudopotential calculations of the vibrational modes of the thionin molecule also indicate the formation of a monolayer of intact thionin molecules. Therefore, the simple functionalization process (involving only mild aqueous solution chemistry) described here works well and can be used to construct smooth monolayers of photoactive molecules with functional amine groups. 相似文献
382.
This paper describes an application of genetic algorithms to the bus driver scheduling problem. The application of genetic algorithms extends the traditional approach of Set Covering/Set Partitioning formulations, allowing the simultaneous consideration of several complex criteria. The genetic algorithm is integrated in a DSS but can be used as a very interactive tool or a stand-alone application. It incorporates the user's knowledge in a quite natural way and produces solutions that are almost directly implemented by the transport companies in their operational planning processes. Computational results with airline and bus crew scheduling problems from real world companies are presented and discussed. 相似文献
383.
Luis Felipe N. Guedes Marcela T. Dalboni Garcia Jéssica N. Cunha Lais T. Duarte Denise Bertagnolli Ladário da Silva José A. O. Huguenin Elivelton Alves Ferreira 《Journal of Solid State Electrochemistry》2016,20(9):2517-2523
In this work, we grow TiO2 nanotube layers by using the single-step direct anodization of Ti-6Al-7Nb alloy in aqueous electrolytes containing F? ions. Nanotube layers are characterized by spectroscopic ellipsometry (SE) and field-emission gun scanning electron microscopy (FEG-SEM). We also use SE to monitor the anodization process for TiO2 nanotube layers on biocompatible Ti-6Al-7Nb alloy. In addition, we study mechanical properties by nanoindentation. 相似文献
384.
A new implementation of the conventional three-dimensional boundary-integral formulation for deformable drops in a viscous medium at low Reynolds numbers is presented. We describe a scheme to generate concentrated emulsions and a numerical procedure for computing interactions among deformable drops. Direct numerical simulations are used to describe the expansion of an ordered emulsion at dispersed-phase volume fraction up to 0.98. We also study the viscoelastic response of a monodisperse emulsion which have been concentrated up to 0.68. The results have demonstrated the feasibility of simulating high-volume fraction emulsions, and the method can readily be extended to explore three-dimensional foam problems. 相似文献
385.
386.
Eliana Alves Nuno Santos Tânia Melo Elisabete Maciel M. Luísa Dória Maria A. F. Faustino João P. C. Tomé Maria G. P. M. S. Neves José A. S. Cavaleiro Ângela Cunha Luisa A. Helguero Pedro Domingues Adelaide Almeida M. Rosário M. Domingues 《Rapid communications in mass spectrometry : RCM》2013,27(23):2717-2728
387.
Vanderléa de Souza Janaína Marques Rodrigues Raquel Duarte da C. Cunha Bandeira Laura A. das Neves Valente Marcus Vinícius Barreto Sousa Viviane Fernandes da Silva Rafael Agostinho Lemos da Silva 《Accreditation and quality assurance》2008,13(12):717-721
This study simulated the transport and storage conditions of ethanol in water certified reference material (CRM) produced
by the Chemical Metrology Division of Inmetro—DQUIM with the purpose of estimating the measurement uncertainty related to
stability. The short-term stability study was performed on five different mass fractions (w) in terms of mg ethanol/g solution of the ethanol in water CRM. The nominal values are w = 0.5, 0.9, 1.1, 3.8 and 4.6 mg/g, at temperatures of 4 and 60 °C. On the other hand, the long-term stability study was developed
on four different mass fractions (nominal values): w = 0.5, 0.9, 1.1 and 4.6 mg/g, at a temperature of 20 °C. This paper will show the data from the long-term stability study
that took place over 52 weeks. The method used complies with ISO Guide 35, the BCR Guideline for Feasibility Studies and ISO
Guide 34. According to the statistical parameters used in both studies, the stability of ethanol in water CRM was confirmed
for all of the mass fractions studied. 相似文献
388.
Carlos Vinicius Barros Oliveira Patric Anderson Gomes da Silva Saulo Relison Tintino Cathia Cecília Coronel Maria Celeste Vega Gomez Mírian Roln Francisco Assis Bezerra da Cunha Maria Flaviana Bezerra Morais-Braga Henrique Douglas Melo Coutinho Abolghasem Siyadatpanah Polrat Wilairatana Jean Paul Kamdem Luiz Marivando Barros Antonia Eliene Duarte Pedro Silvino Pereira 《Molecules (Basel, Switzerland)》2022,27(7)
Weeds are an important source of natural products; with promising biological activity. This study investigated the anti-kinetoplastida potential (in vitro) to evaluate the cytotoxicity (in vitro) and antioxidant capacity of the essential oil of Rhaphiodon echinus (EORe), which is an infesting plant species. The essential oil was analyzed by GC/MS. The antioxidant capacity was evaluated by reduction of the DPPH radical and Fe3+ ion. The clone Trypanosoma cruzi CL-B5 was used to search for anti-epimastigote activity. Antileishmanial activity was determined using promastigotes of Leishmania braziliensis (MHOM/CW/88/UA301). NCTC 929 fibroblasts were used for the cytotoxicity test. The results showed that the main constituent of the essential oil was γ-elemene. No relevant effect was observed concerning the ability to reduce the DPPH radical; only at the concentration of 480 μg/mL did the essential oil demonstrate a high reduction of Fe3+ power. The oil was active against L. brasiliensis promastigotes; but not against the epimastigote form of T. cruzi. Cytotoxicity for mammalian cells was low at the active concentration capable of killing more than 70% of promastigote forms. The results revealed that the essential oil of R. echinus showed activity against L. brasiliensis; positioning itself as a promising agent for antileishmanial therapies. 相似文献
389.
Matilde S. Rodrigues Samira G. Ferreira Csar Quiroz Christopher J. Earley Diego García-Borreguero Rodrigo A. Cunha Francisco Ciruela Attila Kfalvi Sergi Ferr 《Molecules (Basel, Switzerland)》2022,27(5)
Brain iron deficiency (BID) constitutes a primary pathophysiological mechanism in restless legs syndrome (RLS). BID in rodents has been widely used as an animal model of RLS, since it recapitulates key neurochemical changes reported in RLS patients and shows an RLS-like behavioral phenotype. Previous studies with the BID-rodent model of RLS demonstrated increased sensitivity of cortical pyramidal cells to release glutamate from their striatal nerve terminals driving striatal circuits, a correlative finding of the cortical motor hyperexcitability of RLS patients. It was also found that BID in rodents leads to changes in the adenosinergic system, a downregulation of the inhibitory adenosine A1 receptors (A1Rs) and upregulation of the excitatory adenosine A2A receptors (A2ARs). It was then hypothesized, but not proven, that the BID-induced increased sensitivity of cortico-striatal glutamatergic terminals could be induced by a change in A1R/A2AR stoichiometry in favor of A2ARs. Here, we used a newly developed FACS-based synaptometric analysis to compare the relative abundance on A1Rs and A2ARs in cortico-striatal and thalamo-striatal glutamatergic terminals (labeled with vesicular glutamate transporters VGLUT1 and VGLUT2, respectively) of control and BID rats. It could be demonstrated that BID (determined by measuring transferrin receptor density in the brain) is associated with a selective decrease in the A1R/A2AR ratio in VGLUT1 positive-striatal terminals. 相似文献
390.