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排序方式: 共有159条查询结果,搜索用时 15 毫秒
1.
AbstractGeneralized thermoelastic interactions due to three-phase-lag time-nonlocal heat transfer in a Kelvin-Voigt type infinitely extended visco-thermoelastic continuum with cylindrical cavity has been investigated. The two-temperature generalized thermoelasticity theory has also been taken into account. The problem has been solved in the domain of Laplace on the assumption that the surface of the cavity is free from traction and is subjected to a smooth and time-dependent-heating effect. Laplace inversion of the transformed solutions has been carried out numerically. The obtained numerical data for different considerations are plotted in graphs to study the effects of time-nonlocal parameter, two-temperature parameter and visco-thermoelastic relaxation parameter on different thermoelastic quantities of physical interest. 相似文献
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The authors prepared surface modified (with polyelectrolyte layers), tea polyphenols (TPP) encapsulated, gelatin nanoparticles (TPP‐GNP) and characterised them. The size of the spherical nanoparticles was ∼50 nm. Number of polyelectrolyte layers and incubation time influenced the encapsulation efficiency (EE); highest EE was noted in nanoparticles with six polyelectrolyte layers (TPP‐GNP‐6L) incubated for 4 h. TPP released from TPP‐GNP‐6L in simulated biological fluids indicated protection and controlled release of TPP due to encapsulation. Mathematical modelling indicated anomalous type as a predominant mode of TPP release. TPP‐GNP‐6L exhibited enhanced pharmacokinetics in rabbit model compared with free TPP. The area under the concentration‐time curve and mean residence time were significantly higher in TPP‐GNP‐6L compared with free TPP which provide an evidence of higher bioavailability of TPP due to encapsulation. The authors demonstrated that encapsulation of TPP into GNPs favoured slow and sustained release of TPP with improved pharmacokinetics and bioavailability thereby can prolong the action of TPP.Inspec keywords: gelatin, nanoparticles, encapsulation, biomedical materials, nanomedicine, particle size, polymer electrolytes, polymer films, nanofabricationOther keywords: bioavailability, pharmacokinetics, gelatin nanoparticles, surface modified tea polyphenols, polyelectrolyte layers, spherical nanoparticle size, incubation time, encapsulation efficiency, TPP‐GNP‐6L, simulated biological fluids, mathematical modelling, TPP release, rabbit model, concentration‐time curve, mean residence time, time 4 h 相似文献
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Preserving individual privacy when publishing data is a problem that is receiving increasing attention. Thanks to its simplicity the concept of k-anonymity, introduced by Samarati and Sweeney [1], established itself as one fundamental principle for privacy preserving data publishing. According to the k-anonymity principle, each release of data must be such that each individual is indistinguishable from at least k−1 other individuals. 相似文献
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Peter Wanke Md. Abul Kalam Azad C. P. Barros Abdollah Hadi‐Vencheh 《Expert Systems》2016,33(3):213-229
This paper presents a performance assessment of 88 Association of Southeast Asian Nations banks from 2010 to 2013, using an integrated three‐stage approach on financial criteria that emulates the CAMELS rating system. More precisely, fuzzy analytic hierarchy process is used first to assess the relative weights of a number of criteria related to capital adequacy (C), asset quality (A), management quality (M), earnings (E), liquidity (L), and sensitivity to market risk (S) based on the opinion of 88 Association of Southeast Asian Nations experts. Then, these weights are used as technique for order of preference by similarity to ideal solution inputs to assess their relative efficiency. Lastly, neural networks are combined with technique for order of preference by similarity to ideal solution results to produce a model for banking performance with effective predictive ability. The results reveal that contextual variables have a prominent impact on efficiency. Specifically, parsimony in equity leveraging derived from Islamic finance principles may be the underlying cause in explaining higher efficiency levels. 相似文献
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Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. New insights into the pathogenesis of this lethal disease are urgently needed. Chromosomal copy number alterations (CNAs) can lead to activation of oncogenes and inactivation of tumor suppressors in human cancers. Thus, identification of cancer-specific CNAs will not only provide new insight into understanding the molecular basis of tumor genesis but also facilitate the identification of HCC biomarkers using CNA. 相似文献
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Mohammad Abul Hossain Shahidul Islam Farzana A. Chowdhury Tariq G. Mohiuddin Koji Uchida Takahiro Tamura 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(1):43-51
We studied the elemental analysis, structural morphology, mechanical, and electrical properties of carbon nanoparticles synthesized from diesel. The spherical carbon particle size in the range of about 10 to 80 nm in diameter was observed in scanning electron microscope (SEM) studies that were identified by Atomic force microscopy (AFM) study as an aggregation of carbon particles of average size 2.5 nm. The surface rms of carbon nanoparticle thin film (CNTF) was measured directly by AFM and found 0.22 nm. The Derjaguin–Muller–Toporov (DMT) elastic modulus of carbon nanoparticles (CNPs) was measured by PeakForce QNM mode of AFM. The minimum and maximum elastic modulus was measured of 0.40 GPa and 43.89 GPa, respectively. The resistivity, conductivity, magneto resistance, mobility, and average Hall co-efficient were measured by “Ecopia Hall-effect measurement system” by four-point Van der Pauw approach at ambient condition. We demonstrated I–V characteristic at the Indium/CNTF thin film interface, which is accompanied by rectifying behavior. 相似文献
8.
Photocatalytic conversion of CO2 into methanol using graphitic carbon nitride under solar,UV laser and broadband radiations 下载免费PDF全文
Photocatalytic conversion of carbon dioxide into methanol using highly efficient g‐C3N4, in conjunction with three different radiations (solar radiation, broad‐band ultraviolet (UV)–visible lamp, and laser beam) is presented. The optical, structural, and morphological properties of the synthesized g‐C3N4 were studied using advanced analytical techniques like Fourier transform infrared spectroscopy, UV–visible spectrometer, X‐ray diffraction, high‐resolution transmission electron microscopy, high‐angle annular dark field, and X‐ray photoelectron spectroscopy. The relative merits of the three sources of radiation in the presence of g‐C3N4 were studied in terms of key figures of merit of the photocatalytic process, namely, methanol production yield and quantum yield. As expected, after 40 min of irradiation, 355‐nm laser (40 mJ/pulse, 10 Hz) with g‐C3N4 rendered the best methanol production yield (510 μmol g ? 1 h ? 1), followed by solar radiation (130 μmol g ? 1 h ? 1), and UV broadband lamp. This indicates that the photon flux and the spectral properties of incident light are the key factors for the enhancement of methanol production yield. Although the methanol production yield with 355‐nm laser radiation is quite impressive because of the inherent high photon flux and the monochromatic nature of laser, the methanol yield of 130 μmol g ? 1 h ? 1 with natural sunlight is quite an important result, as it can be used for the development of large‐scale solar fuel generation facilities by harnessing the naturally abundant solar radiation. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
9.
Alessandro C. Martins Lais BukmanAlexandro M.M. Vargas Érica O. BarizãoJuliana C.G. Moraes Jesuí V. VisentainerVitor C. Almeida 《Food chemistry》2013
This study proposes a FRAP assay adapted to FIA system with a merging zones configuration. The FIA system conditions were optimised with the response surface methodology using the central composite rotatable design. The optimisation parameters studied were: the carrier flow rate, the lengths of the sample and reagent loops, and reactor length. The conditions selected in accordance with the results were: carrier flow rate of 1.00 ml/min, length of the loops 18.2 cm and length of the reaction coil 210.1 cm. The detection and quantification limits were, respectively, 28.6 and 86.8 μmol/l Fe2+, and the precision was 1.27%. The proposed method had an analytical frequency of 30 samples/h and about 95% less volume of FRAP reagent was consumed. The FRAP assay adapted to the FIA system under the optimised conditions was utilised to determine the antioxidant activity of tea samples. 相似文献
10.
Luciane Madureira Almeida Juliana Ferreira Floriano Thuanne Pires Ribeiro Lais Nogueira Magno Lígia Souza Lima Silveira da Mota Nei Peixoto Fátima Mrué Paulo Melo-Reis Ruy de Souza Lino Junior Carlos Frederico de Oliveira Graeff Pablo José Gonçalves 《Journal of materials science. Materials in medicine》2014,25(9):2153-2162
The latex obtained from Hancornia speciosa is used in folk medicine for treatment of several diseases, such as acne, warts, diabetes, gastritis and inflammation. In this work, we describe the biocompatibility assessment and angiogenic properties of H. speciosa latex and its potential application in medicine. The physical–chemical characterization was carried out following different methodologies (CHN elemental analyses; thermogravimetric analyses and Fourier transform infrared spectroscopy). The biocompatibility was evaluated through cytotoxicity and genotoxicity tests in fibroblast mouse cells and the angiogenic properties were evaluated using the chick chorioallantoic membrane (CAM) assay model. The physical–chemical results showed that the structure of Hancornia speciosa latex biomembrane is very similar to that of Hevea brasiliensis (commercially available product). Moreover, the cytotoxicity and genotoxicity assays showed that H. speciosa latex is biocompatible with life systems and can be a good biomaterial for medical applications. The CAM test showed the efficient ability of H. speciosa latex in neovascularization of tissues. The histological analysis was in accordance with the results obtained in the CAM assay. Our data indicate that the latex obtained from H. speciosa and eluted in water showed significant angiogenic activity without any cytotoxic or genotoxic effects on life systems. The same did not occur with H. speciosa latex stabilized with ammonia. Addition of ammonia does not have significant effects on the structure of biomembranes, but showed a smaller cell survival and a significant genotoxicity effect. This study contributes to the understanding of the potentialities of H. speciosa latex as a source of new phytomedicines. 相似文献