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81.
We present Laplace field microscopy as a method for generating intrinsic contrast of transparent specimens. This technique uses a spatial light modulator to perform the Laplacian of the field in the Fourier plane of a microscope image. The resulting image incorporates phase information and thus renders high contrast images from phase objects. We demonstrate the potential of the method by imaging index-matched beads, unlabeled tissue slices, and dynamic live cells. 相似文献
82.
R. Cristescu C. PopescuA.C. Popescu S. GrigorescuI.N. Mihailescu A.A. CiucuS. Iordache A. AndronieI. Stamatin E. Fagadar-CosmaD.B. Chrisey 《Applied Surface Science》2011,257(12):5293-5297
We report the deposition by MAPLE of metallized nanostructured (5,10,15,20-tetraphenyl)porphinato manganese(III) chloride thin films onto gold screen-printed electrodes, or 〈1 1 1〉 Si substrates. The deposited nanostructures were characterized by atomic force microscopy and exhibited globular structures with average diameters decreasing with laser fluence. Raman spectroscopy showed that no major decomposition appeared. We have investigated the Mn(III)-metalloporphyrin thin films by cyclic voltammetry in order to evaluate the potential bio/chemosensing activity on dopamine neurotransmitter analyte. We have found that the manganese(III)-porphyrin is appropriate as a single mediator for dopamine sensing in the specific case of gold screen-printed electrodes. 相似文献
83.
In this paper we develop a theoretical model for the magnetically induced optical anisotropy in dense magnetic colloids made of spherical and un-aggregated magnetic monodomain nanoparticles. Both dipole-field and dipole-dipole magnetic and electric interactions between the magnetic monodomain particles are taken into account in the Hamiltonian of the system. Using the pair correlation function in a colloidal suspension of magnetic nanoparticles developed by Ivanov and Kuznetsova (2001) [11], the complex dielectric constant of a magnetic colloid is modeled as a function of the light polarization direction, the magnetic field intensity and magnetic particle concentration and diameter. The two main features of the model are that, on the one hand, it predicts the possibility of magnetically induced optical anisotropy in dense magnetic colloids made of spherical and un-aggregated monodomain nanoparticles, and on the other hand, unlike the existing models for diluted samples, it predicts a non-linear dependence of dichroism and birefringence on magnetic particle concentration. 相似文献
84.
In the present paper, we deal with the complex Szasz-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on compact disks. Also, the exact order of approximation is found. 相似文献
85.
Ovidiu Popescu 《Applied Mathematics Letters》2011,24(1):1-4
The aim of this paper is to extend a very recent result proved by Dori? (2009) [4], as well as other theorems given by Rhoades (2001) [2] and Dutta and Choudhury (2008) [3]. 相似文献
86.
Improved Iterative Version of the Coats-Redfern Method to Evaluate Non-Isothermal Kinetic Parameters 总被引:1,自引:0,他引:1
An improved version of the Coats-Redfern method of evaluating non-isothermal kinetic parameters is presented. The Coats-Redfern approximation of the temperature integral is replaced by a third-degree rational approximation, which is much more accurate. The kinetic parameters are evaluated iteratively by linear regression and, besides the correlation coefficient, the F test is suggested as a supplementary statistical criterion for selecting the most probable mechanism function. For applications, both non-isothermal data obtained by theoretical simulation and experimental data taken from the literature for the non-isothermal dehydration of Mg(OH)2 have been processed.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
87.
88.
The kinetic parameters of dehydration were determined under non-isothermal conditions for different polystyrenedivinylbenzene
sulfonic acid type cationites (DVB) and their dependence on the degree of cross-linking granulation, porosity, specific surface,
content of SO3M groups (M=Li, Na, K, Rb), nature of the alkali metal in partially neutralized -SO3H groups and heating rate was investigated.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
Ion Grosu Lo?c Toupet Gerard Plé Sorin Mager Eugen Mesaros Andreea Varga Elena Bogdan 《Monatshefte für Chemie / Chemical Monthly》2000,54(5):277-286
The synthesis and stereochemistry of new dibrominated spiro-1,3-dioxane derivatives are reported. Investigations by means
of NMR methods and single crystal X-ray diffraction for two compounds revealed the high regio- and diastereoselectivity of
the bromination reaction of some new spiro-1,3-dioxanes and the asymmetric induction of the chiral carbon atom located in
the spiro skeleton. 相似文献
90.
Andrei Popescu 《Mathematical Logic Quarterly》2004,50(3):265-280
The paper proposes a flexible way to build concepts within fuzzy logic and set theory. The framework is general enough to capture some important particular cases, with their own independent interpretations, like “antitone” or “isotone” concepts constructed from fuzzy binary relations, but also to allow the two universes (of objects and attributes) to be equipped each with its own truth structure. Perhaps the most important feature of our approach is that we do not commit ourselves to any kind of logical connector, covering thus the case of a possibly non‐commutative conjunction too. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献