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101.
102.
He X Zhou L Nesterenko EP Nesterenko PN Paull B Omamogho JO Glennon JD Luong JH 《Analytical chemistry》2012,84(5):2351-2357
For the first time, graphitized carbon particles with a high surface area have been prepared and evaluated as a new material for probing direct electrochemistry of hemoglobin (Hb). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) imaging revealed that the carbon monolithic skeleton was constructed by a series of mesopores with irregular shapes and an average pore diameter of ~5.6 nm. With a surface area of 239.6 m(2)/g, carbon particles exhibited three major Raman peaks as commonly observed for carbon nanotubes and other carbon materials, i.e., the sp(3) and sp(2) carbon phases coexisted in the sample. A glassy carbon electrode modified with carbon monoliths and didodecyldimethylammonium bromide exhibited direct electron transfer between Hb molecules and the underlying electrode with a transfer rate constant of 6.87 s(-1). The enzyme electrode displayed a pair of quasi-reversible reduction-oxidation peaks at -0.128 and -0.180 V, reflecting the well-known feature of the heme [Fe(3+)/Fe(2+)] redox couple: a surface-controlled electrochemical process with one electron transfer. This reagentless biosensing approach was capable of detecting H(2)O(2), a simple molecule but plays an important role in analytical and biological chemistry, as low as 0.1 μM with linearity of 0.1-60 μM and a response time of <0.8 s, comparing favorably with other carbon based electrodes (5 s). 相似文献
103.
Motornov M Malynych SZ Pippalla DS Zdyrko B Royter H Roiter Y Kahabka M Tokarev A Tokarev I Zhulina E Kornev KG Luzinov I Minko S 《Nano letters》2012,12(7):3814-3820
A reversible locking mechanism is established for the generation of anisotropic nanostructures by a magnetic field pulse in liquid matrices by balancing the thermal energy, short-range attractive and long-range repulsive forces, and dipole-dipole interactions using a specially tailored polymer shell of nanoparticles. The locking mechanism is used to precisely regulate the dimensions of self-assembled magnetic nanoparticle chains and to generate and disintegrate three-dimensional (3D) nanostructured materials in solvents and polymers. 相似文献
104.
Ekaterina Shemyakova 《Programming and Computer Software》2012,38(2):105-108
The paper is devoted to the Darboux transformations, an effective algorithm for finding analytical solutions of partial differential
equations. It is proved that Wronskian-like formulas suggested by G. Darboux for the second-order linear operators on the
plane describe all possible differential transformations with M of the form D
x
+ m(x, y) and D
y
+ m(x, y), except for the Laplace transformations. 相似文献
105.
106.
Ekaterina A. Litus Alexey S. Kazakov Evgenia I. Deryusheva Ekaterina L. Nemashkalova Marina P. Shevelyova Aliya A. Nazipova Maria E. Permyakova Elena V. Raznikova Vladimir N. Uversky Sergei E. Permyakov 《International journal of molecular sciences》2021,22(11)
Prevention of amyloid β peptide (Aβ) deposition via facilitation of Aβ binding to its natural depot, human serum albumin (HSA), is a promising approach to preclude Alzheimer’s disease (AD) onset and progression. Previously, we demonstrated the ability of natural HSA ligands, fatty acids, to improve the affinity of this protein to monomeric Aβ by a factor of 3 (BBRC, 510(2), 248–253). Using plasmon resonance spectroscopy, we show here that another HSA ligand related to AD pathogenesis, serotonin (SRO), increases the affinity of the Aβ monomer to HSA by a factor of 7/17 for Aβ40/Aβ42, respectively. Meanwhile, the structurally homologous SRO precursor, tryptophan (TRP), does not affect HSA’s affinity to monomeric Aβ, despite slowdown of the association and dissociation processes. Crosslinking with glutaraldehyde and dynamic light scattering experiments reveal that, compared with the TRP-induced effects, SRO binding causes more marked changes in the quaternary structure of HSA. Furthermore, molecular docking reveals distinct structural differences between SRO/TRP complexes with HSA. The disintegration of the serotonergic system during AD pathogenesis may contribute to Aβ release from HSA in the central nervous system due to impairment of the SRO-mediated Aβ trapping by HSA. 相似文献
107.
Francesca Terenziani Claudine Katan Ekaterina Badaeva Sergei Tretiak Mireille Blanchard‐Desce 《Advanced materials (Deerfield Beach, Fla.)》2008,20(24):4641-4678
Functional organic materials with enhanced two‐photon absorption lead to new technologies in the fields of chemistry, biology, and photonics. In this article we review experimental and theoretical methodologies allowing detailed investigation and analysis of two‐photon absorption properties of organic chromophores. This includes femtosecond two‐photon excited fluorescence experimental setups and quantum‐chemical methodologies based on time‐dependent density functional theory. We thoroughly analyze physical phenomena and trends leading to large two‐photon absorption responses of a few series of model chromophores focusing on the effects of symmetric and asymmetric donor/acceptor substitution and branching. 相似文献
108.
Vladimir V. Chesnokov Alexander F. Bedilo Ekaterina I. Shuvarakova 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(5):402-406
AbstractС/Al2O3 and C/MgO carbon-mineral composites were synthesized by propane decomposition over Al2O3 at 600–650?°C and MgO carbonization in 1,3-butadiene at 600?°C. The synthesized carbon-mineral composites were studied by EPR, XRD and transmission electron microscopy. It was found that a mosaic structure of carbon clusters was formed on the internal surface of the oxides and gradually grew until it covered its whole surface. A method for synthesis of graphene materials by using MgO as a template followed by its dissolution in hydrochloric acid was suggested. A maximum was observed on the dependence of the graphene surface area on the carbon concentration in the composites. The highest specific surface area of the synthesized graphene about 1800–1900?m2/g was observed for the samples obtained from C-MgO composites containing 8–10?wt.% C. 相似文献
109.
Jiehan?ZhouEmail author Ekaterina?Gilman Juha?Palola Jukka?Riekki Mika?Ylianttila Junzhao?Sun 《Personal and Ubiquitous Computing》2011,15(3):291-303
Incorporating service composition and pervasive computing into managing users’ complex everyday activities calls for the Pervasive
Service Composition paradigm for everyday life. In this paper, we propose the concept of Context-Aware Pervasive Service Composition
(CAPSC), which aims at enabling a pervasive system to provide user service compositions that are relevant to the situation
at hand. We investigate CAPSC requirements and design a CAPSC architecture by taking into account context-aware peer coordination,
context-aware process service adaptation, and context-aware utility service adaptation. We present a proof of concept application
prototype as well. 相似文献
110.
For nonlinear systems, feedback control strategies have to be parameterized in such a way that they guarantee asymptotic stability in a certain neighborhood of desired operating points or desired trajectories. Due to not exactly known initial conditions, parameter uncertainties, and measurement errors characterizing dynamic system models in real applications, interval techniques are taken into consideration in this paper to verify stability properties of nonlinear uncertain systems with continuous-time dynamics. These techniques aim at a computation of guaranteed regions of attraction for asymptotically stable equilibria. The practical applicability is shown for the analysis of tracking controllers for ship motions in an uncertain environment. In this application, we focus on analyzing the effects of parameter uncertainties on the domains in the state-space that can be proven to belong to the region of attraction of the desired equilibrium. 相似文献