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101.
Anand Kumar Sharma Narender Kumar Kaushik 《Monatshefte für Chemie / Chemical Monthly》1983,114(4):399-405
A series of [Cp 2ZrL]+[ROCS2]? complexes whereL is the conjugate base of acetylacetone, benzoylacetone or 8-hydroxyquinoline andR=Me,Et ori-Pr have been synthesised in aqueous medium by the reaction of [Cp 2ZrL]+Cl? withROCS 2 ? K+. Various physico-chemical studies carried out for these complexes indicate that all the complexes are 1:1 electrolytes in which the ligandL is bidentate, consequently there is a tetrahedral coordination about the zirconium atom. 相似文献
102.
Sundararaman A Zakharov LN Rheingold AL Jäkle F 《Chemical communications (Cambridge, England)》2005,(13):1708-1710
The unsupported organocopper pyridine complexes C6F5Cu(py) (2) and [C6F5Cu]2(4,4'-bipy) (3) form supramolecular structures that are unprecedented in organocopper chemistry; one-dimensional chains of copper atoms with Cu...Cu distances of 2.8924(3) angstroms in the blue-luminescent complex are likely associated with cuprophilic interactions, whereas multiple perfluoroarene-arene interactions dominate in the supramolecular assembly of 3. 相似文献
103.
104.
Anand Pillay 《Annals of Pure and Applied Logic》1980,43(2):147-160
We prove that if T is a stable theory with only a finite number (>1) of countable models, then T contains a type-definable pseudoplane. We also show that for any stable theory T either T contains a type-definable pseudoplane or T is weakly normal (in the sense of [9]). 相似文献
105.
The high energy gamma-ray flux (energy greater than 1012 eV) resulting from high energy protons interacting with photons of the recently observed sub-millimeter microwave radiation in metagalactic space is calculated. Comparison of the flux of these gamma-rays with experimental observations indicate that the observed sub-millimeter radiation may not be universal. 相似文献
106.
In this paper we consider the inverse problem for bounded Jacobi matrices with nonempty absolutely continuous spectrum and
as an application show the almost periodicity of some random Jacobi matrices. We do the inversion in two different ways. In
the general case we use a direct method of reconstructing the Green functions. In the special case where we show the almost
periodicity, we use an alternative method using the trace formula for points in the orbit of the matrices under translations.
This method of reconstruction involves analyzing the Abel-Jacobi map and solving of the Jacobi inversion problem associated
with an infinite genus Riemann surface constructed from the spectrum. 相似文献
107.
Acid-catalyzed condensation of furan and pentafluorobenzaldehyde yielded conjugated macrocycles with six and eight furan rings. They represent systems similar to annulenes with 30pi and 40pi electrons. From their structural analyses, it was found that furan rings in both the molecules were inverted in an alternative fashion and displayed nontwisted conformations. [structure: see text]. 相似文献
108.
Optofluidic devices offer flexibility for a variety of tasks involving biological specimen. We propose a system for three-dimensional (3D) sensing and identification of biological micro-organisms. This system consists of a microfluidic device along with a digital holographic microscope and relevant statistical recognition algorithms. The microfluidic channel is used to house the micro-organisms, while the holographic microscope and a CCD camera record their digital holograms. The holograms can be computationally reconstructed in 3D using a variety of algorithms, such as the Fresnel transform. Statistical recognition algorithms are used to analyze and identify the micro-organisms from the reconstructed wavefront. Experimental results are presented. Because of computational reconstruction of wavefronts in holographic imaging, this technique offers unique advantages that allow one to image micro-organisms within a deep channel while removing the inherent microfluidic-induced aberration through interferometery. 相似文献
109.
Asokan K Tsai HM Bao CW Chiou JW Pong WF Sonia G Anand TJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(2):454-457
X-ray absorption spectroscopic measurements have been used to compare the electronic structures of swift heavy ions (100 MeV Si ions) irradiated and pristine Ni-Al nanocrystalline films. Results from X-ray diffraction (XRD), X-ray absorption near-edge structure (XANES) spectra at Al K-, and Ni L(2,3)-edges and extended X-ray absorption fine structure (EXAFS) at Ni K-edges are discussed. The observed XRD peaks indicate the improvement of crystalline nature and Al(111) clustering after the swift heavy ion interactions. While the XANES spectra at Ni L(2,3)-edges show decrease in the intensity of white line strength, the Al K-edge shows increase in intensity after irradiation. Above results imply that swift heavy ions induce low Z (i.e., Al) ion mass transport, changes in Al sp-Ni-d hybridization, and charge transfer. EXAFS results show that crystalline nature is improved after swift heavy irradiation which is consistent with XRD results. 相似文献
110.
We investigate a simple model for equilibrium deformation of a sheet with concentration-dependent elasticity. The model is motivated by several physical situations where deformation of a sheet is modulated by concentration of a mobile species, for example, a quasi-2D array of carbon nanotubes. Elasticity of the sheet is modeled using a free energy functional that includes concentration-dependent potential energies, and a free energy of mixing. We show that the sheet responds to imposed distortion by rearranging its constituents and can do so in a smooth and stable manner only for sufficiently small distortion. For larger distortions, through phase plane and numerical analysis, we consider how the system can meet boundary conditions through nonsmooth solutions. 相似文献