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91.
Luminita?AndronicEmail author Diana?Andrasi Alexandru?Enesca Maria?Visa Anca?Duta 《Journal of Sol-Gel Science and Technology》2011,58(1):201-208
A comparative study of TiO2 powders prepared by sol–gel methods is presented. Titanium tetraisopropoxide was used as the precursor for the sol–gel processes.
The effects of the annealing treatment on phase, crystallite size, porosity and photodegradation of dyes (methyl orange and
methylene blue) were studied. The phase structure, microstructure and surface properties of the films were characterized by
using X-ray diffraction (XRD) and Atomic Force Microscopy (AFM). The X-ray diffraction was used for crystal phase identification,
for the accurate estimation of the anatase–rutile ratio and for the crystallite size evaluation of each polymorph in the samples.
It was found that the only TiO2 anatase phase of the synthesized TiO2 develops below 500 °C, between 600 and 800 °C the anatase coexist with rutile and above 800 °C only the rutile phase was
found in the samples. Attention has been paid not only to crystal structures, but also to the porosity, the particle size
and the photocatalytic properties. However, the annealing temperature was found to have significant influence on the photocatalytic
properties. Different TiO2 doctor blade thin films were obtained mixing the sol gel powder (100% anatase) and TiO2 Aldrich with TiO2 Degussa P25. The surfactant (Triton X100 or sodium dodecyl sulfate) affects the packing density of the particles during deposition
and the photocatalytic degradation efficiency of the dyes. The photocatalytic degradation kinetics of methyl orange and methylene
blue using TiO2 thin film were investigated. 相似文献
92.
Charge transfer interactions in mixtures of poly(9-vinylcarbazole) with three nitro compounds (4,4′dinitrodibenzyl, ethyl
3,5-dinitrobenzoate and 2,2′,4,4′-tetranitrodibenzyl) were examined. 相似文献
93.
Thomas M Wishart David G Brownstein Derek Thomson Anca M Tabakova Katherine M Boothe Jack W Tsao Thomas H Gillingwater 《BMC neuroscience》2009,10(1):148-8
Background
The slow Wallerian Degeneration (Wld S ) gene specifically protects axonal and synaptic compartments of neurons from a wide variety of degeneration-inducing stimuli, including; traumatic injury, Parkinson's disease, demyelinating neuropathies, some forms of motor neuron disease and global cerebral ischemia. The Wld S gene encodes a novel Ube4b-Nmnat1 chimeric protein (WldS protein) that is responsible for conferring the neuroprotective phenotype. How the chimeric WldS protein confers neuroprotection remains controversial, but several studies have shown that expression in neurons in vivo and in vitro modifies key cellular pathways, including; NAD biosynthesis, ubiquitination, the mitochondrial proteome, cell cycle status and cell stress. Whether similar changes are induced in non-neuronal tissue and organs at a basal level in vivo remains to be determined. This may be of particular importance for the development and application of neuroprotective therapeutic strategies based around Wld S -mediated pathways designed for use in human patients. 相似文献94.
Adina Morozan Anca Dumitru Claudia Nastase Florin Nastase Ioan Stamatin 《Macromolecular Symposia》2008,267(1):129-133
Confidence in the potential of hydrogen as an energy vector and fuel bring the opportunities for enhancing electrolyzer performance. The aim of this paper is to develop new polymer nanocomposites as electrolyte membranes for PEM-electrolyzer. A series of nanocomposite membranes, including GEFC/TiO2, GEFC/CNTs, and GEFC/TiO2CNTs have been developed and characterized by FT-IR spectroscopy and AFM. The application of polymer nanocomposite membranes in electrochemical cells for water electrolysis was investigated. Experimental results obtained with respect to performance are reported and discussed related to GEFC membrane. 相似文献
95.
M. Agop P. E. Nica P. D. Ioannou A. Antici V. P. Paun 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,49(2):239-248
The scale relativity model was extended for the motions on fractal curves of fractal dimension D F and third order terms in the equation of motion of a complex speed field. It results that, in a fractal fluid, the convection, dissipation and dispersion are compensating at any scale (differentiable or non-differentiable), whereas a generalized Schrödinger type equation is obtained for an irrotational movement of the fractal fluid. For D F = 2 and the dissipative approximation of the motions, the fractal model of atom is build: the real part of the complex speed field describes the electron motion on stationary orbits according to a quantification condition, while the imaginary part of the complex speed field gives the electron energy quantification. For D F = 3 and the dispersive approximation of motions, some properties of the matter are explained: at the differentiable scale the flowing regimes (non-quasi-autonomous and quasi-autonomous) of the fractal fluids are separated by the experimental “0.7 structure”, while for the non-differentiable scale the fractal potential acts as an energy accumulator and controls through coherence the transport phenomena. Moreover, the compatibility between the differentiable and non-differentiable scales implies a Cantor space-time, and consequently a fractal at any scale. Thus, some properties of the matter (the anomaly of nano-fluids thermal conductivity, the superconductivity etc.) can be explained by this model. 相似文献
96.
M. Agop Camelia Popa Anca Harabagiu 《理论物理通讯》2008,50(11):1197-1204
Considering the fractal structure of space-time, the scale relativity theory in the topological dimension DT = 2 is built. In such a conjecture, the geodesics of this space-time imply the hydrodynamic model of the quantum mechanics. Subsequently, the gauge gravitational field on a fractal space-time is given. Then, the gauge group, the gauge-covariant derivative, the strength tensor of the gauge field, the gauge-invariant Lagrangean, the field equations of the gauge potentials and the gauge energy-momentum tensor are determined. Finally, using this model, a Reissner- Nordstrom type metric is obtained. 相似文献
97.
Anca Radulescu 《Journal of statistical physics》2008,130(2):373-385
This paper adds a computational approach to a previous theoretical result illustrating how the complexity of a simple dynamical
system evolves under deformations. The algorithm targets topological entropy in the 2-dimensional family P
Q
of compositions of two logistic maps. Estimation of the topological entropy is made possible by the correspondence between
P
Q
and a subfamily of sawtooth maps P
T
, and is based on the well-known fact that the kneading-data of a map determines its entropy. A complex search for kneading-data
in P
T
turns out to be computationally fast and reliable, delivering good entropy estimates. Finally, the algorithm is used to produce
a picture of the entropy level-sets in P
Q
, as illustration to theoretical results such as Hu (Ph.D. thesis, CUNY, 1995) and Radulescu (Discrete Cont. Dyn. Syst. 19(1):139–175, 2007). 相似文献
98.
Anca Suteanu-Simulescu Alina Diana Zamfir Raluca Ica Mirela Sarbu Cristian V. A. Munteanu Florica Gadalean Adrian Vlad Flaviu Bob Dragos Catalin Jianu Ligia Petrica 《Molecules (Basel, Switzerland)》2022,27(9)
Considering the valuable information provided by glycosphingolipids as molecular markers and the limited data available for their detection and characterization in patients suffering from Type 2 diabetic kidney disease (DKD), we developed and implemented a superior method based on high-resolution (HR) mass spectrometry (MS) and tandem MS (MS/MS) for the determination of gangliosides in the urine of DKD patients. This study was focused on: (i) testing of the HR MS and MS/MS feasibility and performances in mapping and sequencing of renal gangliosides in Type 2 DM patients; (ii) determination of the changes in the urine gangliosidome of DKD patients in different stages of the disease—normo-, micro-, and macroalbuminuria—in a comparative assay with healthy controls. Due to the high resolution and mass accuracy, the comparative MS screening revealed that the sialylation status of the ganglioside components; their modification by O-acetyl, CH3COO−, O-fucosyl, and O-GalNAc; as well as the composition of the ceramide represent possible markers for early DKD detection, the assessment of disease progression, and follow-up treatment. Moreover, structural investigation by MS/MS demonstrated that GQ1d(d18:1/18:0), GT1α(d18:1/18:0) and GT1b(d18:1/18:0) isomers are associated with macroalbuminuria, meriting further investigation in relation to their role in DKD. 相似文献
99.
100.
Anca Visinescu 《Physics letters. A》1994,190(5-6):425-428
The three soliton contribution to the specific heat of a classical easy-plane ferromagnet chain is calculated using asymptotic methods from the theory of differential equations depending on a large parameter. 相似文献