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981.
J.H. KooD.H. Ji S.C. WonJu H. Park 《Communications in Nonlinear Science & Numerical Simulation》2012,17(8):3399-3405
This paper proposes an improved robust delay-dependent criterion for stability of genetic regulatory networks with delays which vary in an interval. A modified Lyapunov-Krasovskii functional is used to derive a sufficient condition in terms of linear matrix inequalities (LMIs) which can be easily solved by various convex optimization algorithms. The derived stability criterion is less conservative than ones in the literature. A numerical example and simulation results show the effectiveness of the proposed method. 相似文献
982.
Voltammetry of immobilized microparticles (VMP) has been used in this work for the quantitative determination of tin and lead particles in their binary alloys. Carbon paste electrodes, which contained small amounts of tin and lead or their mixtures, were used as working electrodes and square wave voltammograms of each electrode were recorded. Quantification was performed using optimum experimental conditions, obtained by an experimental design technique. The calibration was made by measuring the percentage peak height of each metal taking the sum of peak currents of the both metals as 100 %. The results were compared with quantitative results of X‐ray fluorescence (XRF) technique to evaluate the capability of VMP method in its quantitative determination of solid samples. 相似文献
983.
Tobias Fieback Frieder DreisbachMarcus Petermann Roland SpanEckard Weidner 《Fluid Phase Equilibria》2011,301(2):217-224
A novel measuring method is presented here that allows sorption and solvation measurements near to different process conditions. Especially for the sorption kinetics it is important that the measuring conditions are similar to later applications. Particularly for high pressure sorption measurements this claim could not be fulfilled for most technical applications.The advantage of the measuring methods presented here is that solid bed samples in high pressure gravimetry can be measured under flow-through conditions in both directions and, for the first time in high pressure gravimetry, liquid samples can be measured under flow-through conditions. Especially for ionic liquids, of which a large variety of new substances with unknown sorption potentials have been synthesised in the last few years, this results in much shorter measuring times.The first measurements presented here show that the new system allows for measuring times around 26 times shorter for an ionic liquid. 相似文献
984.
We construct the transfer matrix for the open chain with the centrally extended SU(2|2) symmetry attached to the so called Z=0 giant graviton brane. Using the reflection equations, unitarity property and crossing property, we show that this model is integrable. 相似文献
985.
Xinjiao Bai 《Applied Surface Science》2010,256(8):2327-1104
Hollow carbon nitride microspheres have been synthesized using a novel liquid phase electrodeposition technique. The microspheres are composed of numerous nanoparticles with size of about 5-30 nm. The diameters of the spheres range from 800 nm to 1.1 μm, and shell thickness is about 80-250 nm. This is the first attempt to synthesize carbon nitride with specific nanostructure by the electrodeposition method, which is proved to be facile and effective, and can be performed in an atmospheric environment and at a rather low temperature. The hollow carbon nitride may have potential applications as lubrication, catalysis, biomolecule adsorption, drug delivery, electronic materials, etc. in the future. 相似文献
986.
This note studies the iterative solutions to the coupled Sylvester-transpose matrix equation with a unique solution. By using the hierarchical identification principle, an iterative algorithm is presented for solving this class of coupled matrix equations. It is proved that the iterative solution consistently converges to the exact solution for any initial values. Meanwhile, sufficient conditions are derived to guarantee that the iterative solutions given by the proposed algorithm converge to the exact solution for any initial matrices. Finally, a numerical example is given to illustrate the efficiency of the proposed approach. 相似文献
987.
L. Gavrila FlorescuE. Vasile I. SanduI. Soare C. FleacaR. Ianchis C. LuculescuE. Dutu R. BirjegaI. Morjan I. Voicu 《Applied Surface Science》2011,257(12):5270-5273
The work presents preliminary studies with the goal to extend the share of long graphene ribbons in laser-synthesized carbon black. Investigations revealed the existence, as a major constituent, of graphene ribbons composed of up to 10-15 graphene layers, spaced at ∼0.35-0.37 nm and of tens of nanometres in length. The samples used to study the development of this specific structure were obtained from sensitized acetylene-based mixtures and the experiments were performed following the variation of both the experimental parameters and gas composition. 相似文献
988.
In this work we employ the state-of-the-art pseudopotential method, within a generalized gradient approximation to the density functional theory, combined with a recently developed method for the calculation of HREELS spectra to study a series of different proposed models for carbon incorporation on the silicon (0 0 1) surface. A fully discussion on the geometry, energetics and specially the comparison between experimental and theoretical STM images and electron energy loss spectra indicate that the Si(1 0 0)-c(4 × 4) is probably induced by Si-C surface dimers, in agreement with recent experimental findings. 相似文献
989.
《Analytical letters》2012,45(5):849-865
Abstract In this paper we report on the construction principle and performance of an amperometric 3-enzyme sensor for sucrose based on crystalline bacterial cell surface layers (S-layers) as immobilization matrix for the biological components. Isoporous, crystalline surface layers (S-layers) have been identified as outermost cell envelope layer in many bacteria. Since they are composed of identical protein or glycoprotein subunits with functional groups in well defined positions and orientations, they represent ideal matrices for the controlled and reproducible immobilization of functional macromolecules, as required for the development of biosensors. Apart from single enzyme sensors, which were described earlier, a strikingly simple method for the assembly and optimization of multistep systems was developed. For the fabrication of an amperometric sucrose sensor invertase, mutarotase and glucose oxidase were individually immobilized on S-layer fragments isolated from Clostridium thermohydrosulfuricum L111-69 via aspartic acid as spacer molecules. Subsequently, appropriate mixtures of enzyme loaded S-layer fragments were deposited on a microfiltration membrane and finally, the composite multifunctional sensing layer was sputtered with gold in order to establish a good metal contact. Amperometric sucrose measurements based on H2O2 oxidation revealed a high signal level (1 μA?1/cm2?mmol sucrose), 5 min response time and a linear range up to 30 mM sucrose as the main characteristics of the S-layer sucrose sensor. 相似文献
990.