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排序方式: 共有906条查询结果,搜索用时 15 毫秒
61.
Ignacio Moreno-Villoslada Felipe González Luis Arias José Miguel Villatoro Ricardo Ugarte Susan Hess Hiroyuki Nishide 《Dyes and Pigments》2009,82(3):401-408
The aggregation behavior of C.I. Basic Violet 10 in the presence of poly(sodium 4-styrenesulfonate) was modified, as a consequence of short-range interactions. In aqueous acidic media, the cationic dye forms hydrophobic ion pairs with polymeric benzene sulfonate groups which tend to aggregate in H-contacts, this tendency being readily influenced by the relative concentration of the macromolecule with respect to that of the dye. In the case of dilute aqueous dye solutions (≤10?4 M), for which the probability of dye self-aggregation is small, C.I. Basic Violet 10 self-contacts are forced in the presence of a moderate excess of poly(sodium 4-styrenesulfonate). At dye concentrations >10?4 M, for which the probability of dye self-aggregation increases, dye-dye contacts are minimized in the presence of a large excess of the polymer. Hence, the luminescence of dye solutions can be tuned insorar as, that of dilute dye solutions is quenched whilst that of concentrated dye solutions can be enhanced. This behavior was not observed for other polyelectrolytes such as poly(sodium vinylsulfonate), or the more hydrophobic poly(sodium 2-(N-acrylamido)-2-methyl-propanesulfonate). 相似文献
62.
Martina Rudnicki Marcos Roberto de Oliveira Tiago da Veiga Pereira Flávio Henrique Reginatto Felipe Dal-Pizzol José Cláudio Fonseca Moreira 《Food chemistry》2007,100(2):719-724
The leaves of Passiflora alata Dryander and Passiflora edulis Sims, traditionally used in American countries to treat both anxiety and nervousness by folk medicine, are rich in polyphenols, which have been reported as natural antioxidants. In this study, the antioxidant activities of P. edulis and P. alata hydroalcoholic leaf extracts were verified in in vitro and ex vivo assays. P. alata showed a higher total reactive antioxidant potential than did P. edulis. The antioxidant activities of both extracts were significantly correlated with polyphenol contents. In addition, both extracts attenuated ex vivo iron-induced cell death, quantified by lactate dehydrogenase leakage, and effectively protected against protein damage induced by iron and glucose. These findings demonstrate that the P. alata and P. edulis leaf extracts have potent in vitro and ex vivo antioxidant properties and might be considered as possible new sources of natural antioxidants. 相似文献
63.
This article focuses on the relationship between theoretical orientation and clinical practice in Argentina. Five hundred twenty-five psychotherapists were surveyed in the city of Buenos Aires and the provinces of Buenos Aires, Santa Fe, La Pampa, Neuquén, Chubut, and Rio Negro. Psychoanalysis was chosen by 53.1% of the psychotherapists as the main theory used in their clinical practice. Integrationists made up 39.8% of the sample and represented the 2nd most important group. Within the integrationist group, psychoanalysis was mentioned by 63.2% as the main or base theory, followed by 12.9% mentioning cognitive theory. A longitudinal analysis shows how the trend toward integration of the different theories has grown over the years. These results reveal the importance of psychoanalysis and the trend toward integration within clinical practice in Argentina. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
T Genzini A de Oliveira e Silva MP de Miranda CR de Melo RJ Felipe TE dos Santos ES Cardoso CF Costa-Filho RG Haetinger EC Pereira 《Canadian Metallurgical Quarterly》1995,32(4):162-167
Hemangiomas are the most common benign vascular tumor found in the liver. In this study, 103 cases of hepatic hemangiomas were analysed in a retrospective manner. Image aspects such as those seen in ultrassonography, computed tomography, nuclear magnetic resonance and arteriography are discussed. The incidence was higher amongst the female sex, between individuals from 40 to 60 years old, which presented predominantly without symptoms (66%) and localized mainly in the right hepatic lobe (74%). The meaning of those aspects, when adopted, permits the clinicians to differentiate benign from malignant nodular lesions in the liver. 相似文献
65.
Felipe M. Pait 《Systems & Control Letters》1998,35(1):381
We propose a tuner, suitable for adaptive control and (in its discrete-time version) adaptive filtering applications, that sets the second derivative of the parameter estimates rather than the first derivative as is done in the overwhelming majority of the literature. 相似文献
66.
M. A. S. Barrozo C. A. S. Felipe D. J. M. Sartori J. T. Freire 《Drying Technology》2006,24(4):415-422
The present work describes and analyzes Brazilian research related to the quality of soybean seeds dried in moving bed dryers. The main process variables were drying air temperature, relative humidity and velocity, and solid flow rate. The statistical methodology used allowed the achievement of empirical equations for predicting the quality of soybean seeds (germination, vigor, and fissures) in two classical configurations of the moving bed: countercurrent and crosscurrent. The results show that the increase of the seed coat cracking is associated to conditions that lead to a high drying rate. Germination and vigor reduction is also associated to the overdrying conditions. 相似文献
67.
RS Jesuino Rde B Soares SM Salem-Izacc M Pereira MS Felipe CM Soares 《Canadian Metallurgical Quarterly》1997,41(2):93-99
The reversed dermal graft has been employed in reconstructive plastic surgery for almost 80 years. It is recommended that the dermatologic surgeon use this graft technique whenever a case calls for the combined advantages of the split-thickness skin graft for poorly vascularized areas and the axial pedicle flap appropriate to areas subject to marked mechanical strain. We present cases in which defects on the scalp, sole, palm, and great toe have been covered by reversed dermal graft and split-thickness skin graft in a single operation with excellent results. Our modification of the technique has proved that simultaneous grafting with reversed dermis and split-thickness skin graft produces satisfactory results, reduces postoperative care by 2 weeks, and obviates repeated anesthesia. 相似文献
68.
Adler Nancy E.; David Henry P.; Major Brenda N.; Roth Susan H.; Russo Nancy Felipe; Wyatt Gail E. 《Canadian Metallurgical Quarterly》1992,47(10):1194
Psychological research is increasingly involved in debates regarding abortion. While recognizing the diversity of ethical and moral issues intertwined with abortion, the American Psychological Association (APA) has focused its involvement on psychological factors, most recently by appointing an expert panel to review the literature on psychological effects. This article notes the history of APA involvement and reports on the panel's conclusions. It presents evidence that abortion is not likely to be followed by severe psychological responses and that psychological aspects can best be understood within a framework of normal stress and coping rather than a model of psychopathology. Correlates of more negative responses following abortion are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Sergio Neves Monteiro Regina Coeli M. P. Aquino Felipe Perisse D. Lopes 《Journal of Materials Science》2008,43(2):489-493
Natural lignocellulosic fibers are successfully replacing synthetic fibers as the reinforcement phase of composite materials
in many engineering applications, including automobile parts. In addition to well-known conventional lignocellulosic fibers,
others with promising properties, like that obtained from the leaves of the curaua plant (Ananas erectifolius) found in the Amazon region of Brazil, are now being considered. The present work investigated microstructural aspects associated
with the performance of curaua fibers in pullout tests carried out to characterize the fibers interfacial strength with a
polyester matrix. The results have shown that the naturally bonded filaments that constitute a curaua fiber present interspatial
voids between them. These voids play an important role in providing adherence of the fiber surface to a polyester matrix,
resulting in an effective reinforcement for a curaua-strengthened composite. 相似文献
70.
Felipe Guerrero-Barba II Miguel A. Cabrerizo-Vílchez Miguel A. Rodríguez-Valverde 《Journal of Materials Science》2014,49(22):7723-7729
In hot asphalt applications, the adhesion between bitumen and mineral aggregate is usually described in terms of bitumen surface tension and contact angle of the bitumen over the aggregate. However, the quantification of the physico-chemical bond between bitumen and aggregate under realistic conditions is a nontrivial task. In this work, we designed a high-temperature goniometer to measure the contact angle of liquid bitumen on mineral aggregate substrates. The drop deposition was conducted once the thermal equilibrium between liquid bitumen and aggregate was attained. We monitored the spreading of sessile drops of viscous naphthenic bitumen and asphaltic bitumen on polished sheets of calcareous aggregates at high temperature (70–100 °C). A near complete wetting with very low contact angles (13– \(24^{\circ }\) ) was reproduced regardless of the bitumen origin and temperature. Furthermore, the coating degree of the naphthenic and asphaltic bitumens on the calcareous aggregates at high temperature was apparently similar. We found that the bitumen-aggregate adhesion is adequately described by dynamic spreading rather than by equilibrium wettability. Spreading kinetics was ruled by the particular properties of each bitumen such as viscosity and acid index. We found evidences of acid etching of the naphthenic bitumen on the calcareous aggregates during spreading at high temperature. 相似文献