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排序方式: 共有149条查询结果,搜索用时 46 毫秒
61.
62.
Morjan Iuliana P. Alexandrescu Rodica Morjan Ion Luculescu Catalin Vasile Eugeniu Osiceanu Petre Scarisoreanu Monica Demian Gabriela 《Journal of nanoparticle research》2013,15(11):1-11
Series of self-assembled and mono-dispersed bovine serum albumin (BSA)-conjugated ZnS/CuS nano-composites with different Zn/Cu ratios had been successfully synthesized by a combination method of the biomimetic synthesis and ion-exchange strategy under the gentle conditions. High-resolution transmission electron microscopy observation, Fourier transform infrared spectra and zeta potential analysis demonstrated that BSA-conjugated ZnS/CuS nano-composites with well dispersity had the hierarchical structure and BSA was a key factor to control the morphology and surface electro-negativity of final products. The real-time monitoring by atomic absorption spectroscopy and powder X-ray diffraction revealed that the Zn/Cu ratio of nano-composites could be controlled by adjusting the ion-exchange time. In addition, the metabolic and morphological assays indicated that the metabolic proliferation and spread of rat pheochromocytoma (PC12) cells could be inhibited by nano-composites, with the high anti-cancer activity at a low concentration (4 ppm). What were more important, Zn and Cu in nano-composites exhibited a positive cooperativity at inhibiting cancer cell functions. The microscope observation and biochemical marker analysis clearly revealed that the nano-composites-included lipid peroxidation and disintegration of membrane led to the death of PC12 cells. Summarily, the present study substantiated the potential of BSA-conjugated ZnS/CuS nano-composites as anti-cancer drug. 相似文献
63.
64.
Irina-Claudia Grig-Alexa Iuliana Simionescu Oana-Irina Patriciu Stéphane Massip Adriana-Luminita Fînaru Christian Jarry Jean-Michel Léger Gérald Guillaumet 《Tetrahedron letters》2012,53(15):1885-1888
The formation of alkoxy substituted di(pyridin-2-yl)amines and N-arylpyridin-2-ylamines by nitro group reduction is described. Unexpected substitution of ortho with the amino at C-6 was observed during the reduction using SnCl2·2H2O in different alcohols. The influence of the nature of the atom at the 3- and 5-positions of nitro-substituted di(pyridin-2-yl)amines and N-arylpyridin-2-ylamines was investigated. 相似文献
65.
Iuliana Mihaela Jipa Anicuta Stoica Marta Stroescu Loredana-Mihaela Dobre Tanase Dobre Sorin Jinga Christu Tardei 《Chemical Papers》2012,66(2):138-143
Active packaging materials are the subject of research because their performance exceeds that of traditional packaging. From
this class, antimicrobial materials extend the shelf-life of products and reduce the risk of contamination by pathogens. In
this paper, new composite materials with antimicrobial properties are obtained by using polyvinyl alcohol and bacterial cellulose
powder. Potassium (2E,4E)-hexa-2,4-dienoate was used as the antimicrobial agent. The films thus obtained were characterised using Fourier-transform
infrared spectroscopy and scanning electron microscopy. Mass transfer phenomena concerning the release of potassium (2E,4E)-hexa-2,4-dienoate were investigated. The results indicated that the new biocomposite films could be used as antimicrobial
packaging materials. 相似文献
66.
67.
Mihalache Valentina Mercioniu Ionel Aldica Gheorghe Pasuk Iuliana 《Journal of Thermal Analysis and Calorimetry》2018,132(1):463-469
Journal of Thermal Analysis and Calorimetry - Azobenzenes undergo reversible trans–cis photo-isomerization and have been studied extensively as photo-responsive materials. Despite their... 相似文献
68.
Iuliana Stanculescu 《Annali dell'Universita di Ferrara》2008,54(1):145-168
This report studies an abstract approach to modeling the motion of large eddies in a turbulent flow. If the Navier-Stokes
equations (NSE) are averaged with a local, spatial convolution type filter, , the resulting system is not closed due to the filtered nonlinear term . An approximate deconvolution operator D is a bounded linear operator which is an approximate filter inverse
Using this general deconvolution operator yields the closure approximation to the filtered nonlinear term in the NSE
Averaging the Navier-Stokes equations using the above closure, possible including a time relaxation term to damp unresolved
scales, yields the approximate deconvolution model (ADM)
Here , χ ≥ 0, and w
* is a generalized fluctuation, defined by a positive semi-definite operator. We derive conditions on the general deconvolution
operator D that guarantee the existence and uniqueness of strong solutions of the model. We also derive the model’s energy balance.
The author is partially supported by NSF grant DMS 0508260. 相似文献
69.
Iuliana Spiridon 《Polymer Degradation and Stability》2008,93(10):1884-1890
A study of the enzymatic degradation of some montmorillonite-containing nanocomposites of poly(vinyl alcohol) with starch was based on the determinations of mass loss and the reducing sugars. The degraded residues have been examined by FT-IR spectroscopy and optical microscopy. It has been established that the nanoparticles hinder degradation, while the susceptibility to enzymatic degradation varies in the order: PVA/starch/nanocore > PVA/starch/Bentonite > PVA/starch/Peruvian clay. 相似文献
70.
S. Ilie S. Jipa D. Ilie R. Setnescu J. Paun I. Mihalcea A. Nicolescu 《Journal of Radioanalytical and Nuclear Chemistry》1990,140(1):3-13
The present paper reports correlations between data obtained by the radiothermoluminescence (RTL) method and the catalytic activity of active aluminas. The correlations between the intensity of RTL signals, glow peak temperatures and activation energy obtained by RTL and the data referring to the history, catalytic activity and activation energy of the catalyzed reaction, require the use of RTL as a supplementary method in the characterization of catalysts. The results underline the role of structural defects in the catalyst (or support) on the catalysis as illustrated by the present model. 相似文献