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101.
de Souza FF dos Santos MC dos Passos DC Lima EC Guillo LA 《Journal of nanoscience and nanotechnology》2011,11(9):7603-7610
Curcumin is a natural product possessing therapeutic properties but the low water solubility of this compound limits its use. We have successfully incorporated curcumin into a bilayer of dodecanoic acid attached to magnetite nanoparticles in an effort to maximize solubility and delivery efficiency. Curcumin/magnetite nanoparticles were characterized using diffused reflectance infra-red fourier transform spectroscopy (DRIFTS) and X-ray powder diffraction (XRD). Moreover curcumin associated magnetite nanoparticles inhibited in vitro melanoma cell growth. An inhibitory concentration (IC50) of 66.0 +/- 3.0 microM (48 +/- 2.2 microg-iron/mL) was observed for the curcumin/magnetite nanoparticles. Fluorescent microscopy revealed that curcumin associated magnetite nanoparticles were internalized by the melanoma cells and remained in the cytoplasm. The curcumin/magnetic nanoparticles synthesized in this study possess magnetic and water solubility properties making this a novel curcumin formulation with therapeutic potential. 相似文献
102.
R Zucchi 《Canadian Metallurgical Quarterly》1996,93(1):200-202
103.
Vansteenwegen Debora; Francken Geert; Vervliet Bram; De Clercq Armand; Eelen Paul 《Canadian Metallurgical Quarterly》2006,32(1):71
A well-demonstrated phenomenon in traditional Pavlovian conditioning research with humans is that of experimental extinction. In contrast, human evaluative conditioning research suggests that evaluative learning shows marked resistance to extinction. Here, the authors replicate both findings concurrently. Two differential fear conditioning experiments with an electrocutaneous stimulus as the unconditioned stimulus evidenced (a) sensitivity to extinction using an autonomic skin-conductance measure and (b) complete resistance to extinction using an affective-priming measure. The results corroborate the idea that evaluative conditioning is more resistant to extinction than is expectancy learning (F. Baeyens, P. Eelen, & G. Crombez, 1995). (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
104.
Qualitative and quantitative characterisation of the lipid fraction of bouillon cubes 总被引:1,自引:0,他引:1
Francesco Caponio Tommaso Gomes Debora Delcuratolo 《European Food Research and Technology》2002,215(3):200-203
An experimental investigation was performed to characterise the fat fraction of bouillon cubes. Besides the routine analyses, the analytical methods used were: silica-gel column chromatography to separate polar compounds, high performance size-exclusion chromatography (HPSEC) for the qualitative and quantitative determination of the single classes of substances constituting the polar compounds, and gas chromatography to determine the acid composition and the trans isomers of unsaturated fatty acids. The fats blended into the bouillon preparations were highly variable and were mainly made up of refined vegetable oils that had undergone hardening, by hydrogenation in most cases. Determination of the free fatty acids and of the peroxide values yielded figures that in some cases exceeded the limits set for the commercialisation of refined vegetable oils. Compared to the routine analyses, the HPSEC analysis of the polar compounds provided a better evaluation of the level of degradation of the fat extracted from the bouillon formulations. The levels of oxidative and hydrolytic degradation were rather high, and similar to those reported for poor quality oils. Analyses of the trans isomers of oleic acid yielded particularly high values (even over 20%) and differentiated the cubes on the basis of the type of fat added. 相似文献
105.
I Biunno IB Rogozin V Appierto L Milanesi M Mostardini S Mumm R Pergolizzi I Zucchi G De Bellis 《Canadian Metallurgical Quarterly》1997,8(1-2):1-15
This paper presents detailed analysis of the entire sequence of a cosmid clone, 26H7, containing 35 kb of human DNA. This cosmid resides on the q27.1 region of the human X chromosome between, DXS1232 and DXS119 loci. Novel potential small exons were detected for which conventional gene identification strategies (Northern blot analysis and extensive cDNA library screening) proved to be inefficient. Of the standard repetitive elements we found: 8 Alu's making up 6.2% of the sequence; 10 MIR segments (4.1%); 5 LINE1 elements (4.8%), 3 MIR2 (1.0%); 2 MLT (2.9%), and 1 MSTA (0.7%) representing about 20% of the total sequence. The overall GC content was rather low, only 42% and no CpG island was detected using rare restriction enzymes. However, a CpG-rich region was identified. Computer aided analysis of the sequence inferred the presence of three possible genes: one of them was found to be homologous to the U7 RNA family elements; a second is reported in this paper, however at the moment no significant homology has been found in the data bank. The third predicted gene has not as yet been found to be detectable by RT-PCR. We also report in this paper the identification of X-chromosome specific repeated sequences. 相似文献
106.
The efficiency of some organic additives for SCC inhibition of AISI 304 stainless steel in 1 M HCl solution can be demonstrated by the Slow Strain Rate (SSR) technique. 1 M HCl solution is the most aggressive solution for the SCC of AISI 304 stainless steel. The most suitable strain rate for studying SCC by the SSR method has been found to be 1 × 10−6s−1. Some organic additives have been tested as SCC inhibitors under the above conditions. Phenylthiourea (PTU), benzimidazole-2-thiol (BIT) and benzothiazole-2-thiol (BTT) have been found to inhibit SCC in stainless steel, thus confirming previous results obtained with a different technique. The inhibitive action of these substances can be attributed to their inhibiting effect on the anodic reaction of metal dissolution. 相似文献
107.
Salthouse Timothy A.; Legg Scott; Palmon Roni; Mitchell Debora R. 《Canadian Metallurgical Quarterly》1990,5(1):9
Adults in their 50s were compared with adults in their late teens or 20s in the accuracy of relatively simple reasoning decisions involving varying amounts of information. Because the magnitude of the age differences in decision accuracy was independent of the amount of information relevant to the decision, it was suggested that adults in their 20s and 50s do not differ in the effectiveness of integrating information across multiple premises. However, the 2 groups differed in the accuracy of trials involving only a single relevant premise, and thus it was inferred that 1 factor contributing to reasoning differences within the age range from 20 to 60 may be a failure to encode, or retain, relevant information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Armentano I Dottori M Puglia D Kenny JM 《Journal of materials science. Materials in medicine》2008,19(6):2377-2387
Nanocomposite films based on single wall carbon nanotubes (SWNTs) and poly(dl-lactide-co-glycolide) copolymer (50:50 PLGA) were processed and analyzed. The purpose of this study was to investigate the effect of
different functionalization systems on the physical stability and morphology of PLGA films. Both covalent and non covalent
functionalization of carbon nanotubes were considered in order to control the interactions between PLGA and SWNTs and to understand
the role of the filler in the biodegradation properties. Using a solvent casting process, different PLGA/SWNT nanocomposites
were prepared and incubated using organic solution under physiological conditions. In-vitro degradation studies were conducted
by measurements of weight loss, infrared spectroscopy, glass transition temperature and SEM observations as a function of
the incubation time, over a 9-week period. All PLGA films were degraded by hydrolitical degradation. However, a different
degradation mechanism was observed in the case of functionalized SWNTs with respect to pristine material. It has been observed
that system composition and SWNT functionalization may play a crucial role on the autocatalytic effect of the degradation
process. These studies suggest that the degradation kinetics of the films can be engineered by varying carbon nanotube (CNT)
content and functionalization. The combination of biodegradable polymers and CNTs opens a new perspective in the self-assembly
of nanomaterials and nanodevices. 相似文献
109.
Vincenzo Esposito Debora Marani Eric D. Wachsman Enrico Traversa 《Journal of the American Ceramic Society》2008,91(2):437-443
A new chemical route to synthesize nanostructured lead ruthenium pyrochlore (Pb2 Ru2 O6.5 ) powders was developed. The synthesis was performed starting from a metal nitrate aqueous solution and N , N , N ', N ' tetramethylethylendiamine (TMEDA). The amine, which is a mild basic chelating agent, was able to control the simultaneous precipitation of lead and ruthenium oxo/hydroxides. For the sake of comparison, Pb2 Ru2 O6.5 powders were prepared using the more conventional polymeric precursor method. The new method was effective for the synthesis of nanostructured Pb2 Ru2 O6.5 powders already stable at 400°C and up to 1000°C. 相似文献
110.
Epoxy formulation including an acrylic triblock copolymer adapted for use in filament winding
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Luciana M. Sáiz Antonela B. Orofino Exequiel S. Rodríguez Ileana A. Zucchi Roberto J. J. Williams 《Polymer Engineering and Science》2016,56(10):1153-1159
Commercial triblock copolymers with a poly(butyl acrylate) (PBuA) central block joined to two poly(methyl methacrylate) (PMMA) end blocks (denoted as MAM) or to two random copolymers end blocks based on MMA and N,N′‐dimethylacrylamide (DMA) (denoted as MAM‐N), can be employed as toughening agents for thermoset composites. However, their use in epoxy formulations for filament winding, requiring low viscosities during the fiber‐impregnation step associated with an adequate glass transition temperature of the cured product is not trivial. In this study, we show that a blend of diglycidylether of bisphenol A (DGEBA), 4,4′‐diamino‐3,3′‐dimethyldicyclohexylmethane (3DCM) and benzylamine (BA), with 20% of amine hydrogens provided by BA, and containing 5 wt% MAM, can be used for these purposes. The addition of MAM increased the critical stress intensity factor from 0.63 MPa.m1/2 to 1.0 MPa.m1/2, the glass transition temperature from 138°C to 145°C, and the glassy modulus at 25°C from 2.95 GPa to 3.15 GPa. MAM was a better choice for the envisaged applications than MAM‐N because it led to solutions of lower viscosity. The higher viscosity produced by MAM‐N was explained by specific interactions between the epoxy‐amine solvent and DMA units present in its terminal blocks. POLYM. ENG. SCI., 56:1153–1159, 2016. © 2016 Society of Plastics Engineers 相似文献