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101.
The paper presents a short review on the synthesis, characterisation and selected medical applications of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGL)) microspheres. The soap-free emulsion-polymerisation of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol macromonomer (PGL) in water yielded core-shell microspheres with a low particle-diameter dispersity (ratio of the weight average particle diameter and the number average particle diameter). The interfacial fraction of PGL units, estimated by XPS, was in the range of 0–42 mole % depending on the concentration of the macromonomer in the polymerisation feed. The studies of adsorption of model proteins showed that the surface fraction of adsorbed protein was significantly reduced when the PGL interfacial fraction was higher than 40 mole %. The P(S/PGL) particles with covalently immobilised proteins were used for the preparation of photonic crystal assemblies suitable for applications in optical biosensors and the medical diagnostic test for the detection of Helicobacter pylori antibodies in the blood serum. 相似文献
102.
Algirdas Matijoška Tatjana Charkova Zenonas Kuodis Vladislava Voiciuk Olegas Eicher-Lorka 《Central European Journal of Chemistry》2012,10(1):113-120
The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized. The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy. 相似文献
103.
104.
Ching-Yang Cheng 《Transport in Porous Media》2012,91(3):877-888
This work studies the Soret and Dufour effects on the double-diffusive free convection over a downward-pointing vertical truncated cone with variable wall heat and mass fluxes in fluid-saturated porous media. A coordinate transformation is used to derive the nondimensional boundary-layer governing equations, and the obtained nonsimilar equations are then solved by the cubic spline collocation method. Results for local surface temperature and the local surface concentration are presented as functions of Soret parameters, Dufour parameters, power-law exponents, buoyancy ratios, and Lewis numbers. Results show that increasing the Dufour parameter tends to increase the local surface temperature, while it tends to decrease the local surface concentration. An increase in the Soret number leads to a decrease in the local surface temperature for buoyancy assisting flows, while it leads to an increase in the local surface temperature for buoyancy opposing flows. Increasing the Soret number tends to increase the local surface concentration. Moreover, the local surface temperature and the local surface concentration of the truncated cones with higher power-law exponents are lower than those with lower exponents. 相似文献
105.
P. G. Siddheshwar R. K. Vanishree Anthony Christy Melson 《Transport in Porous Media》2012,92(2):277-288
The effects of temperature-dependent viscosity, gravity modulation and thermo-mechanical anisotropies on heat transport in a low-porosity medium are studied using the Ginzburg–Landau model. The effect of gravity modulation is to decrease the Nusselt number, Nu and variable viscosity leads to increase in Nu. The thermo-mechanical anisotropies have opposite effect on Nu with thermal anisotropy decreasing the heat transport. 相似文献
106.
Antonio Strozzi 《Journal of Elasticity》2012,108(1):119-123
The solution of cylindrical problems is addressed. A series solution is considered of the biharmonic equation, in which the series terms of the stress function Φ are expressions based upon Legendre polynomials and logarithmically singular functions. An explicit form of a polynomial supplementing each logarithmically singular part of the series solution is obtained. 相似文献
107.
We consider the flow of a viscous incompressible fluid in a pipe when the boundary is a deformable shell of Naghdi type. We prove that the corresponding system of partial differential equations has a solution when the deformation of the shell is smooth and small enough. We propose an algorithm that uncouples the unknowns and prove its convergence. 相似文献
108.
We apply the recently improved version of the 0–1 test for chaos to real experimental time series of laser droplet generation process. In particular two marginal regimes of dripping are considered: spontaneous and forced dripping. The outcomes of the test reveal that both spontaneous and forced dripping time series can be characterized as chaotic, which coincides with the previous analysis based on nonlinear time series analysis. 相似文献
109.
When a sensor network is deployed to detect objects penetrating a protected region, it is not necessary to have every point
in the deployment region covered by a sensor. It is enough if the penetrating objects are detected at some point in their
trajectory. If a sensor network guarantees that every penetrating object will be detected by at least k distinct sensors before it crosses the barrier of wireless sensors, we say the network provides k-barrier coverage. In this paper, we develop theoretical foundations for k-barrier coverage. We propose efficient algorithms using which one can quickly determine, after deploying the sensors, whether
the deployment region is k-barrier covered. Next, we establish the optimal deployment pattern to achieve k-barrier coverage when deploying sensors deterministically. Finally, we consider barrier coverage with high probability when
sensors are deployed randomly. The major challenge, when dealing with probabilistic barrier coverage, is to derive critical
conditions using which one can compute the minimum number of sensors needed to ensure barrier coverage with high probability.
Deriving critical conditions for k-barrier coverage is, however, still an open problem. We derive critical conditions for a weaker notion of barrier coverage,
called weak k-barrier coverage. 相似文献
110.
Tamer Ragheb Arthur Nieuwoudt Yehia Massoud 《Analog Integrated Circuits and Signal Processing》2007,51(1):11-17
In this paper, we present an analytical modeling methodology for fully integrated inductively-degenerated CMOS narrow-band
cascode Low Noise Amplifiers (LNA) that captures short channel transistor effects to enable rapid design space exploration
in current and future process technologies. The modeling methodology captures the impact of parasitics on passive components,
ESD-protection structures, and devices to accurately predict both impedance matching and noise figure. Our modeling is suitable
for numerical optimization and fully automated synthesis for LNAs. The results indicate that the methodology models ESD-protected
LNA circuits with 47.9% better accuracy in noise figure when compared with several current analytical modeling techniques
with four orders of magnitude improvement in simulation time over circuit-level simulation. Given its speed and accuracy,
the analytical modeling methodology is well-suited for design space exploration. 相似文献