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121.
Marcelo Augusto Gonçalves Bardi Luci Diva Brocardo Machado 《Radiation Physics and Chemistry》2012,81(9):1332-1335
In the search for alternatives to traditional paint systems solvent-based, the curing process of polymer coatings by ultraviolet light (UV) has been widely studied and discussed, especially because of their high content of solids and null emission of VOC. In UV-curing technology, organic solvents are replaced by reactive diluents, such as monomers. This paper aims to investigate variations on color, gloss and hardness of print inks cured by different UV radiation doses. The ratio pigment/clear coating was kept constant. The clear coating presented higher average values for König hardness than pigmented ones, indicating that UV-light absorption has been reduced by the presence of pigments. Besides, they have indicated a slight variation in function of cure degree for the studied radiation doses range. The gloss loss related to UV light exposition allows inferring that some degradation occurred at the surface of print ink films. 相似文献
122.
The extracellular matrix consists of collagen, proteoglycans and non-collagen proteins. The incidence of obesity and associated diseases is currently increasing in developed countries. Obesity is considered to be a disease of modern times, and genes predisposing to the disease have been identified in humans and animals. The objective of the present study was to compare the morphological and biochemical aspects of the deep digital flexor tendon of lean (Fa/Fa or Fa/fa) and genetically obese (fa/fa) Zucker rats. Ultrastructural analysis showed the presence of lipid droplets in both groups, whereas disorganized collagen fibril bundles were observed in obese animals. Lean animals presented a larger amount of non-collagen proteins and glycosaminoglycans than obese rats. We propose that the overweight and lesser physical activity in obese animals may have provoked the alterations in the composition and organization of extracellular matrix components but a genetic mechanism cannot be excluded. These alterations might be related to organizational and structural modifications in the collagen bundles that influence the mechanical properties of tendons and the progression to a pathological state. 相似文献
123.
Guilherme Peixoto Jorge Luis Rodrigues Pantoja-Filho José Augusto Bolzan Agnelli Marlei Barboza Marcelo Zaiat 《Applied biochemistry and biotechnology》2012,168(3):651-671
This study evaluates the potential for using different effluents for simultaneous H2 and CH4 production in a two-stage batch fermentation process with mixed microflora. An appreciable amount of H2 was produced from parboiled rice wastewater (23.9?mL g?1 chemical oxygen demand [COD]) and vinasse (20.8?mL g?1 COD), while other effluents supported CH4 generation. The amount of CH4 produced was minimum for sewage (46.3?mL g?1 COD), followed by parboiled rice wastewater (115.5?mL g?1 COD) and glycerol (180.1?mL g?1 COD). The maximum amount of CH4 was observed for vinasse (255.4?mL g?1 COD). The total energy recovery from vinasse (10.4?kJ g?1 COD) corresponded to the maximum COD reduction (74.7?%), followed by glycerol (70.38?%, 7.20?kJ g?1 COD), parboiled rice wastewater (63.91?%, 4.92?kJ g?1 COD), and sewage (51.11?%, 1.85?kJ g?1 COD). The relatively high performance of vinasse in such comparisons could be attributed to the elevated concentrations of macronutrients contained in raw vinasse. The observations are based on kinetic parameters of H2 and CH4 production and global energy recovery of the process. These observations collectively suggest that organic-rich effluents can be deployed for energy recovery with sequential generation of H2 and CH4. 相似文献
124.
Ramos CI Santana-Marques MG Ferrer-Correia AJ Barata JF Tomé AC Neves MG Cavaleiro JA Abreu PE Pereira MM Pais AA 《Journal of mass spectrometry : JMS》2012,47(4):516-522
Two new isomeric aminomethyl corrole derivatives of [5,10,15-tris(pentafluorophenyl)corrolato]gallium(III) were synthesized with pyridine (py) molecules as axial ligands. When investigated by electrospray ionization mass spectrometry, in the positive and the negative ion modes, these compounds showed an unusual gas-phase behavior that could be used for their differentiation. In the positive ion mode, the differentiation was achieved through the formation of diagnostic fragment ions formed from [M-py?+?H](+) precursors, by (CH(3) )(2) NH and HF losses. An unusual addition of water to the main fragment ions provides an alternative route for isomer identification. Semi-empirical calculations were performed to elucidate the structures and stabilities of the main ionic species formed in the positive ion mode. In the negative ion mode isomer discrimination is accomplished via the fragmentation of the methoxide adduct ions [M-py?+?CH(3) O](-) through (CH(3) )(2) N(.) and HF losses. 相似文献
125.
A series of benzimidazole-2-thione derivatives was synthesized using a reaction between the macrocyclic aminal 16H,13H-5:12,7:14-dimethanedibenzo[d,i]-[1,3,6,8] tetraazecine (DMDBTA, 5) and various nucleophiles in the presence of carbon disulfide. A full chemical characterization using IR, 1H-, 13C-NMR and GC-MS analyses of the new compounds is provided. These compounds were separated from the reaction mixture by column chromatography (CC) in highly pure form in 15%-51.4% yield. 相似文献
126.
de Souza TP Chaimovich H Fahr A Schweitzer B Agostinho Neto A Cuccovia IM 《Journal of colloid and interface science》2012,371(1):62-72
Interfacial concentrations of chloride and bromide ions, with Li(+), Na(+), K(+), Rb(+), Cs(+), trimethylammonium (TMA(+)), Ca(2+), and Mg(2+) as counterions, were determined by chemical trapping in micelles formed by two zwitterionic surfactants, namely N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS) and hexadecylphosphorylcholine (HDPC) micelles. Appropriate standard curves for the chemical trapping method were obtained by measuring the product yields of chloride and bromide salts with 2,4,6-trimethyl-benzenediazonium (BF(4)) in the presence of low molecular analogs (N,N,N-trimethyl-propane sulfonate and methyl-phosphorylcholine) of the employed surfactants. The experimentally determined values for the local Br(-) (Cl(-)) concentrations were modeled by fully integrated non-linear Poisson Boltzmann equations. The best fits to all experimental data were obtained by considering that ions at the interface are not fixed at an adsorption site but are free to move in the interfacial plane. In addition, the calculation of ion distribution allowed the estimation of the degree of ion coverage by using standard chemical potential differences accounting for ion specificity. 相似文献
127.
Catarina I. V. Ramos M. Graça Santana‐Marques A. J. Ferrer‐Correia Joana F. B. Barata Augusto C. Tomé M. Graça P. M. S. Neves J. A. S. Cavaleiro Paulo E. Abreu Mariette M. Pereira Alberto A. C. C. Pais 《Journal of mass spectrometry : JMS》2012,47(4):516-522
Two new isomeric aminomethyl corrole derivatives of [5,10,15‐tris(pentafluorophenyl)corrolato]gallium(III) were synthesized with pyridine (py) molecules as axial ligands. When investigated by electrospray ionization mass spectrometry, in the positive and the negative ion modes, these compounds showed an unusual gas‐phase behavior that could be used for their differentiation. In the positive ion mode, the differentiation was achieved through the formation of diagnostic fragment ions formed from [M‐py + H]+ precursors, by (CH3)2NH and HF losses. An unusual addition of water to the main fragment ions provides an alternative route for isomer identification. Semi‐empirical calculations were performed to elucidate the structures and stabilities of the main ionic species formed in the positive ion mode. In the negative ion mode isomer discrimination is accomplished via the fragmentation of the methoxide adduct ions [M‐py + CH3O]‐ through (CH3)2 N. and HF losses. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
128.
Grazziela P. Figueredo Nelson F. F. Ebecken Douglas A. Augusto Helio J. C. Barbosa 《Memetic Computing》2012,4(2):135-147
One issue in data classification problems is to find an optimal subset of instances to train a classifier. Training sets that
represent well the characteristics of each class have better chances to build a successful predictor. There are cases where
data are redundant or take large amounts of computing time in the learning process. To overcome this issue, instance selection
techniques have been proposed. These techniques remove examples from the data set so that classifiers are built faster and,
in some cases, with better accuracy. Some of these techniques are based on nearest neighbors, ordered removal, random sampling
and evolutionary methods. The weaknesses of these methods generally involve lack of accuracy, overfitting, lack of robustness
when the data set size increases and high complexity. This work proposes a simple and fast immune-inspired suppressive algorithm
for instance selection, called SeleSup. According to self-regulation mechanisms, those cells unable to neutralize danger tend
to disappear from the organism. Therefore, by analogy, data not relevant to the learning of a classifier are eliminated from
the training process. The proposed method was compared with three important instance selection algorithms on a number of data
sets. The experiments showed that our mechanism substantially reduces the data set size and is accurate and robust, specially
on larger data sets. 相似文献
129.
María F. Beer Guillermo F. Reta Adrin Puerta Augusto E. Bivona Andrs Snchez Alberti Natacha Cerny Emilio L. Malchiodi Carlos E. Tonn Jos M. Padrn Valeria P. Sülsen Osvaldo J. Donadel 《Molecules (Basel, Switzerland)》2022,27(10)
Cancer is one of the most important causes of death worldwide. Solid tumors represent the vast majority of cancers (>90%), and the chemotherapeutic agents used for their treatment are still characterized by variable efficacy and toxicity. Sesquiterpenes are a group of natural compounds that have shown a wide range of biological activities, including cytotoxic and antiparasitic activity, among others. The antiproliferative activity of natural sesquiterpenes, tessaric acid, ilicic acid, and ilicic alcohol and their semisynthetic derivatives against HeLa, T-47D, WiDr, A549, HBL-100, and SW1573 cell lines were evaluated. The effect of the compounds on Trypanosoma cruzi epimastigotes was also assessed. The selectivity index was calculated using murine splenocytes. Derivatives 13 and 15 were the most antiproliferative compounds, with GI50 values ranging between 5.3 (±0.32) and 14 (±0.90) μM, in all cell lines tested. The presence of 1,2,3-triazole groups in derivatives 15–19 led to improvements in activity compared to those corresponding to the starting natural product (3), with GI50 values ranging between 12 (±1.5) and 17 (±1.1) μM and 16 being the most active compound. In relation to the anti-T. cruzi activity, derivatives 7 and 16 obtained from tessaric acid and ilicic acid were among the most active and selective compounds with IC50 values of 9.3 and 8.8 µM (SI = 8.0 and 9.4), respectively. 相似文献
130.
Dr. G. Henrieke Heideman Dr. José Augusto Berrocal Prof. Meike Stöhr Prof. E. W. Meijer Prof. Ben L. Feringa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):207-211
The development of new strategies for the preparation of multicomponent supramolecular assemblies is a major challenge on the road to complex functional molecular systems. Here we present the use of a non-porous self-assembled monolayer from uC33-NDI-uC33 , a naphthalenediimide symmetrically functionalized with unsaturated 33 carbon-atom-chains, to prepare bicomponent supramolecular surface systems with a series of alkoxy-pyrene ( PyrOR ) derivatives at the liquid/HOPG interface. While previous attempts at directly depositing many of these PyrOR units at the liquid/HOPG interface failed, the multicomponent approach through the uC33-NDI-uC33 template enabled control over molecular interactions and facilitated adsorption. The PyrOR deposition restructured the initial uC33-NDI-uC33 monolayer, causing an expansion in two dimensions to accommodate the guests. As far as we know, this represents the first example of a non-porous or non-metal complex-bearing monolayer that allows the stepwise formation of multicomponent supramolecular architectures on surfaces. 相似文献