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排序方式: 共有343条查询结果,搜索用时 15 毫秒
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Joo O. D. Malafatti Marcela P. Bernardo Francys K. V. Moreira Heloisa Ciol Natalia M. Inada Luiz H.C. Mattoso Elaine C. Paris 《先进技术聚合物》2020,31(6):1377-1387
Poly(lactic acid) (PLA) is a versatile, bioabsorbable, and biodegradable polymer with excellent biocompatibility and ability to incorporate a great variety of active agents. Silver sulfadiazine (SDZ) is an antibiotic used to control bacterial infection in external wounds. Aiming to combine the properties of PLA and SDZ, hydrotalcite ([Mg–Al]‐LDH) was used as a host matrix to obtain an antimicrobial system efficient in delivering SDZ from electrospun PLA scaffolds intended for wound skin healing. The structural reconstruction method was successfully applied to intercalate silver sulfadiazine in the [Mg–Al]‐LDH, as evidenced by X‐ray diffraction and thermogravimetric analyses. Observations by scanning electron microscopy revealed a good distribution of SDZ‐[Mg–Al]‐LDH within the PLA scaffold. Kinetics studies revealed a slow release of SDZ from the PLA scaffold due to the intercalation in the [Mg–Al]‐LDH. In vitro antimicrobial tests indicated a significant inhibitory effect of SDZ‐[Mg–Al]‐LDH against Escherichia coli and Staphylococcus aureus. This antibacterial activity was sustained in the 2.5‐wt% SDZ‐[Mg–Al]‐LDH–loaded PLA nanofibers, which also displayed excellent biocompatibility towards human cells. The multifunctionality of the PLA/SDZ‐[Mg–Al]‐LDH scaffold reported here is of great significance for various transdermal applications. 相似文献
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We propose an Analogy Principle in the context of Unary Inductive Logic and characterize the probability functions which satisfy it. In particular in the case of a language with just two predicates the probability functions satisfying this principle correspond to solutions of Skyrms? ‘Wheel of Fortune’. 相似文献
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Laurence Muhr Steve Pontvianne Katalin Selmeczi Cdric Paris Sandrine Boschi‐Muller Laetitia Canabady‐Rochelle 《Journal of separation science》2020,43(11):2031-2041
Some metal‐chelating peptides have antioxidant properties, with potential nutrition, health, and cosmetics applications. This study aimed to simulate their separation on immobilized metal ion affinity chromatography from their affinity constant for immobilized metal ion determined in surface plasmon resonance, both technics are based on peptide‐metal ion interactions. In our approach, first, the affinity constant of synthetic peptides was determined by surface plasmon resonance and used as input data to numerically simulate the chromatographic separation with a transport‐dispersive model based on Langmuir adsorption isotherm. Then, chromatographic separation was applied on the same peptides to determine their retention time and compare this experimental tR with the simulated tR obtained from simulation from surface plasmon resonance data. For the investigated peptides, the relative values of tR were comparable. Hence, our study demonstrated the pertinence of such numerical simulation correlating immobilized metal ion affinity chromatography and surface plasmon resonance. 相似文献
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Vinícius D. Araújo Waldir Avansi Elaine C. Paris Lauro J. Q. Maia Maria I. B. Bernardi 《Journal of Sol-Gel Science and Technology》2011,59(3):488-494
Pb2CrO5 nanoparticles were embedded in an amorphous SiO2 matrix by the sol–gel process. The pH and heat treatment effects were evaluated in terms of structural, microstructural and
optical properties from Pb2CrO5/SiO2 compounds. X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), energy dispersive spectroscopy
(EDS), and diffuse reflectance techniques were employed. Kubelka–Munk theory was used to calculate diffuse reflectance spectra
that were compared to the experimental results. Finally, colorimetric coordinates of the Pb2CrO5/SiO2 compounds were shown and discussed. In general, an acid pH initially dissolves Pb2CrO5 nanoparticles and following heat treatment at 600 °C crystallized into PbCrO4 composition with grain size around 6 nm in SiO2 matrix. No Pb2CrO5 solubilization was observed for basic pH. These nanoparticles were incorporated in silica matrix showing a variety of color
ranging from yellow to orange. 相似文献
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V. Repän M. Laan P. Paris J. Aarik V. Sammelselg 《Czechoslovak Journal of Physics》1999,49(2):217-224
In the paper the results of experimental study of negative corona in a point – plane gap in a dust-free air flow at atmospheric pressure are presented. Both the low current mode (LCM) of the discharge and Trichel pulses are externally triggered by UV light. Close to the inception voltage of Trichel pulses short-duration current spikes appear besides the steady component of the LCM which indicates to the switch-on of Fowler-Nordheim type emission mechanism. At the inception voltage spike – Trichel pulse transition is recorded. The influence of dielectric layers at the cathode on the discharge parameters is discussed. 相似文献
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E.C. Paris M.F.C. Gurgel G.P. Casali T.M. Boschi J.A. Varela 《Journal of Physics and Chemistry of Solids》2010,71(1):12-17
Pb1−xSmxTiO3 (PST) powders with x varying from 0 to 0.1 were obtained by the polymeric precursor method, a soft chemical route. The vibrational properties relating tetragonal to pseudo-cubic phase transition were studied by Raman spectroscopy. The results obtained showed that the phase transition is extremely dependent upon the samarium content and presents a diffuse behavior. Monitoring of the oxygen 2p and titanium 3d orbitals was performed by the periodic mechanical quantum method, revealing the changes that occur with the distribution and contribution of the hybrid orbitals due to the samarium influence. 相似文献