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81.
The optical and mechanical properties of amorphous SiO2 films deposited on soda-lime silicate float glass by reactive RF magnetron sputtering at room temperature were investigated in dependence of the process pressure. The densities of the films are strongly influenced by the process pressure and vary between 2.38 and 1.91 g cm?3 as the pressure changes from 0.27 to 1.33 Pa. The refractive indices of the films shift between 1.52 and 1.37, while the residual compressive stresses in the deposited films vary in the range from 440 to 1 MPa. Hardness and reduced elastic modulus values follow the same trend and decline with the increase of process pressure from 8.5 to 2.2 GPa and from 73.7 to 30.9 GPa, respectively. The abrasive wear resistance decreases with the density of the films.  相似文献   
82.
We report on the experimental verification of quantum non-Gaussian character of a heralded single-photon state with a positive Wigner function. We unambiguously demonstrate that the generated state cannot be expressed as a mixture of Gaussian states. Sufficient information to witness the quantum non-Gaussian character is obtained from a standard photon anticorrelation measurement.  相似文献   
83.
    
The structure of ionic complex [Cp2Ti(L -Met)2]2+[Cl]2 (where Cp = η5-C5H5) possessing C2 symmetry is presented. Discrete cationic units with distorted tetrahedral geometry around the central titanium atom are connected through intermolecular H···Cl bonds between ammonium group protons of α-amino acid ligands and chloride anions. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
84.
    
We report an aptamer biosensing array for thrombin detection by measuring the electrochemical impedance upon aptamer‐protein formation at the surface of CD‐trodes (GCDTs) in the presence of the redox couple [Fe(CN)6]3?/4?. GCDTs are fabricated from recordable compact discs that contain a fine gold layer. The biosensor is constructed by self‐assembling of a thiol‐modified thrombin binding aptamer (TBA) onto a GCDT surface. The sensor reveals good ligand specificity, recognition in a wide range of thrombin concentrations from 20 nM to 1 µM with a limit of detection of 5 nM.  相似文献   
85.
    
Knob  Radim  Gerstmann  Silke  &#;abala  Radom&#;r  Frank  Hartmut 《Chromatographia》2009,69(11):1431-1435

Fused-silica capillaries covalently coated with polypyrrole offer some interesting properties for capillary electrophoresis. The polymeric, surface-bonded coating is chemically stable and reduces the adsorptive properties of the silica surface. At the same time, the weak positive surface charges offer the possibility of creating a strongly anionic surface when poly-sulfates are used as counter-ions. This affords an electroosmotic flow which is largely independent of pH. With sodium dodecyl sulfate in the background electrolyte, this effect is further enhanced. The potential of the approach is demonstrated with the separation of herbicides by micellar electrokinetic chromatography. Repeatability of electroosmotic mobility of less than 1% RSD is achieved.

  相似文献   
86.
Two preconditioning techniques for the numerical solution of linear elasticity problems are described and studied. Both techniques are based on spectral equivalence approach. The first technique consists in an incomplete factorization of the separate displacement component part of the stiffness matrix. The second technique uses an incomplete factorization of the isotropic approximation to the stiffness matrix. Results concerning existence, stability and efficiency of these preconditioning techniques are presented. The efficiency and robustness of the described techniques are illustrated by numerical experiments.  相似文献   
87.
    
As has been pointed out in a study by Cao, there is an erroneous omission in the study by Axelsson, Corollary 3.2 and Proposition 3.2, and the authors thank Zhi‐hao Cao for pointing this out. We mention, however, that these are side results and do not influence the major result of the paper ‘Preconditioning of matrices partitioned in 2 by 2 block form: Eigenvalue estimates and Schwarz DD for mixed FEM’. In this reply, we give a short background to the relations between inverses of saddle point matrices, thereby providing justified references to previous publications of the topic and present a corrected and extended version of Proposition 3.2. This gives an alternative presentation of the statements in the study by Cao, which might be useful for readers. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
88.
Fused-silica capillaries covalently coated with polypyrrole offer some interesting properties for capillary electrophoresis. The polymeric, surface-bonded coating is chemically stable and reduces the adsorptive properties of the silica surface. At the same time, the weak positive surface charges offer the possibility of creating a strongly anionic surface when poly-sulfates are used as counter-ions. This affords an electroosmotic flow which is largely independent of pH. With sodium dodecyl sulfate in the background electrolyte, this effect is further enhanced. The potential of the approach is demonstrated with the separation of herbicides by micellar electrokinetic chromatography. Repeatability of electroosmotic mobility of less than 1% RSD is achieved.  相似文献   
89.
We propose a quantum device that can approximate any projective measurement on a qubit-a quantum "multimeter." The desired measurement basis is selected by the quantum state of a "program register." Two different kinds of programs are considered and in both cases the device is optimized with respect to maximal average fidelity (assuming uniform distribution of measurement bases). Quantum multimeters exhibiting the covariance property are introduced and an optimal covariant multimeter with a single-qubit program register is found. Possible experimental realization of the simplest proposed device is presented.  相似文献   
90.
Some Properties of Residuated Lattices   总被引:1,自引:0,他引:1  
We investigate some (universal algebraic) properties of residuated lattices--algebras which play the role of structures of truth values of various systems of fuzzy logic.  相似文献   
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