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111.
Discrimination and metrology results of microlithographic patterns from top-down SEM images are explored by means of morphological
image analysis. The method relies on the use of various morphological filters on a top down SEM image. The resulted images
are segmented in order to derive a quality factor which discriminates the candidate images as under- or fully-developed. Furthermore,
the fully developed images are processed in order to extract useful measurements. The proposed image analysis methodology
achieves for first time, to the authors’ knowledge, successful off-line discrimination between under-developed and fully-developed
cases. For the latter case, the measuring method relies upon the evaluation of the connected regions in the SEM image after
segmentation. This is expressed by the Useful Threshold Range (UTR), which corresponds to that specific value of connected
regions obtained for the wider range of the threshold. The method is experimentally demonstrated by employing 72 test images
from high resolution patterns. The evaluated critical pattern parameters are found in good agreement to those derived from
on-line procedures. 相似文献
112.
Yue‐Ling Bai Vassilis Tangoulis Prof. Rong‐Bin Huang Prof. Lan‐Sun Zheng Prof. Dr. Jun Tao Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(10):2377-2383
Copper clusters : Two high‐nuclearity copper cages, tricorne Cu21 and saddlelike cyclic Cu16 (see pictures), were synthesized. Magnetic studies and Monte Carlo calculations were also performed to show the overall antiferromagnetic properties of the two compounds.
113.
Ion exchange studies on natural and modified zeolites and the concept of exchange site accessibility 总被引:5,自引:0,他引:5
Inglezakis VJ Loizidou MM Grigoropoulou HP 《Journal of colloid and interface science》2004,275(2):570-576
In the present study natural and Na-rich form of clinoptilolite are examined, in respect to ion exchange of Pb2+, Cu2+, Cr3+, and Fe3+. Equilibrium and kinetic studies performed, under the same normality (0.01 N). Equilibrium studies demonstrate that Na+ enrichment of clinoptilolite is beneficial in respect to metal uptake for all metals, except Cr3+, which is shown to have the same equilibrium behavior in both materials. Kinetic study shows that diffusion coefficients are in the range of 0.16 to 9 x 10(-9) cm2/s, and are not always improved in Na-rich form of clinoptilolite. The effect of temperature on diffusion coefficients is also examined, and Arrhenius activation energy is determined to be in the range of 3.02 to 13.9 kcal/mol, for all metals and materials, except Cu2+, which have extremely low activation energy in the natural sample, equal to 0.04 kcal/mol. 相似文献
114.
Sagnou M Benaki D Triantis C Tsotakos T Psycharis V Raptopoulou CP Pirmettis I Papadopoulos M Pelecanou M 《Inorganic chemistry》2011,50(4):1295-1303
The synthesis and characterization of "2 + 1" complexes of the [M(CO)(3)](+) (M = Re, (99m)Tc) core with the β-diketones acetylacetone (complexes 2, 8) and curcumin (complexes 5, 10 and 6, 11) as bidentate OO ligands, and imidazole or isocyanocyclohexane as monodentate ligands is reported. The complexes were synthesized by reacting the [NEt(4)](2)[Re(CO)(3)Br(3)] precursor with the β-diketone to generate the intermediate aqua complex fac-Re(CO)(3)(OO)(H(2)O) that was isolated and characterized, followed by replacement of the labile water by the monodentate ligand. All complexes were characterized by mass spectrometry, NMR and IR spectroscopies, and elemental analysis. In the case of complex 2, bearing imidazole as the monodentate ligand, X-ray analysis was possible. The chemistry was successfully transferred at (99m)Tc tracer level. The curcumin complexes 5 and 6, as well as their intermediate aqua complex 4, that bear potential for radiopharmaceutical applications due to the wide spectrum of pharmacological activity of curcumin, were successfully tested for selective staining of β-amyloid plaques of Alzheimer's disease. The fact that the complexes maintain the affinity of the mother compound curcumin for β-amyloid plaques prompts for further exploration of their chemistry and biological properties as radioimaging probes. 相似文献
115.
Vassili Kitsios Daniel Rodríguez Vassilis Theofilis Andrew Ooi Julio Soria 《Journal of computational physics》2009,228(19):7181-7196
A methodology based on spectral collocation numerical methods for global flow stability analysis of incompressible external flows is presented. A potential shortcoming of spectral methods, namely the handling of the complex geometries encountered in global stability analysis, has been dealt with successfully in past works by the development of spectral-element methods on unstructured meshes. The present contribution shows that a certain degree of regularity of the geometry may be exploited in order to build a global stability analysis approach based on a regular spectral rectangular grid in curvilinear coordinates and conformal mappings. The derivation of the stability linear operator in curvilinear coordinates is presented along with the discretisation method. Unlike common practice to the solution of the same problem, the matrix discretising the eigenvalue problem is formed and stored. Subspace iteration and massive parallelisation are used in order to recover a wide window of its leading Ritz system. The method is applied to two external flows, both of which are lifting bodies with separation occurring just downstream of the leading edge. Specifically the flow configurations are a NACA 0015 airfoil, and an ellipse of aspect ratio 8 chosen to closely approximate the geometry of the airfoil. Both flow configurations are at an angle of attack of 18° with a Reynolds number based on the chord length of 200. The results of the stability analysis for both geometries are presented and illustrate analogous features. 相似文献
116.
Ioannis Polyzos Georgios Tsigaridas Mihalis Fakis John Parthenios Anastassios Fragos Vassilis Giannetas Peter Persephonis John Mikroyannidis 《Monatshefte für Chemie / Chemical Monthly》2001,457(6):169-175
Two-photon absorption induced fluorescence microscopy was used as a tool for the examination of the spatial distribution of a thin dye film. The two-photon absorption induced fluorescence signal is essentially the same as that produced by excitation with a single photon of equivalent energy. When femtosecond pulses are focused into a sample there is an intrinsic spatial selectivity of the two-photon emission signal, since it is dependent upon the square of the light intensity. This has tremendous implications in fluorescence microscopy. Since two-photon absorption is confined in a small region at the focal waist of an objective lens, photodamage and photobleaching of the sample are significantly reduced. In addition, the two-photon signal has inherent z-axis spatial resolution, which facilitates the construction of 3-D images. In the present work an application of this technique to a thin film of a dye is presented. The method can generally be applied to thin films made from photonic polymers. 相似文献
117.
Mohamed Afif Mhand Hifi Vangelis Th. Paschos Vassilis Zissimopoulos 《The Journal of the Operational Research Society》1995,46(10):1260-1268
We solve approximately the minimum set covering problem by developing a new heuristic, which is essentially based on the flow algorithm originally developed by Ford and Fulkerson. We perform a comparative study of the performances (concerning solution qualities and execution times) of the flow algorithm as well as of the natural greedy heuristic for set covering originally studied by Johnson and Lovász. 相似文献
118.
Wei-Tzou Luh Vassilis Zafiropulos Paul D. Kleiber William C. Stwalley Shawn P. Heneghan 《Journal of Molecular Spectroscopy》1985,111(2):327-343
The gold vapor laser has been used to irradiate the alkali dimers Li2, Na2, K2, and Rb2. Significant fluorescence was found only from Na2 and K2. Six fluorescent series in the A1Σu+-X1Σg+ system of Na2 and three in the B1Πu-X1Σg+ system of K2 were assigned, respectively. New spectroscopic constants for the X1Σg+ state of 39K2 are derived, and new RKR potential energy curves for the X1Σg+ and B1Πu states of 39K2 are given. 相似文献
119.
120.
The 3,5-di-tert-butyl-catecholato and 9,10-phenanthrenecatecholato adducts of the cobalt-tetraazamacrocycle complex Co(Me(4)cyclam)(2+) (Me(4)cyclam = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) were synthesized and oxidized. The oxidation reaction products were isolated in the solid state as hexafluorophosphate derivatives. Both these complexes can be formulated as 1:1 cobalt(II)-semiquinonato complexes, that is, Co(Me(4)cyclam)(DBSQ)PF(6) (1) and Co(Me(4)cyclam)(PhSQ)PF(6) (2), in the temperature range 4-300 K, in striking contrast with the charge distribution found in similar adducts formed by related tetraazamacrocycles. The synthesis strategy and the structural, spectroscopic, and magnetic properties are reported and discussed. The crystallographic data for 2 are as follows: monoclinic, space group P2(1)/a, nomicron. 14, a = 14.087(4) A, b = 15.873(4) A, c = 14.263 (7) A, alpha = 89.91(3) degrees, beta = 107.34(2) degrees, gamma = 90.08(2) degrees, Z = 4. Both these complexes are characterized by triplet electronic ground states arising from the antiferromagnetic coupling between the high-spin d(7) metal ion and the radical ligand. 相似文献