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101.
We give a possible mechanism for periodically occurring phaseslips in Aharonov–Bohm oscillations of mesoscopic rings. 相似文献
102.
An elegant analytic method is presented to derive a modified form of the Ornstein-Zernike equation which not only solves the
statistical mechanical problem for hard rods and spheres but can be used to find solutions for arbitrary non-vanishing direct
correlation functions. 相似文献
103.
A novel approach to energy dependent phase shift analysis ofππ scattering is proposed. Optimised polynomial expansions of Roskies’ amplitudes are given. The parameters of these expansions
are searched out by making a fit to the differential cross-sections. Then the transformation matrix between Roskies’ amplitudes
and the conventional partial waves is used to compute the phase shifts and inelasticities. Significant improvement is observed
in so far as the number of free parameters for a fixed energy phase shift analysis is concerned. Value for the effective Chew-Mandelstam
coupling constant, λCM, is also estimated. 相似文献
104.
105.
In the present study, five different invert trap configurations (rectangular with and without lids on both sides; trapezoidal, trapezoidal with rectangular base and rectangular with trapezoidal base with lids on both sides) were simulated for both two-dimensional (2D) and three-dimensional (3D) flow conditions for three sediment types (sand, styrocell and plastic beads) at six flow rates (0.35, 0.70, 1.05, 1.35, 4.55 and 9.95 L/s) for each trap. Computational fluid dynamics (CFD)-based modeling using FLUENT software with Renormalization Group (RNG) k-e model along with discrete phase model (DPM) were used in the simulations. A hexagonal/tetrahedral and map-type non-uniform grid was chosen to discretize the entire computational domain and a control volume finite difference method was used to solve the governing equations. The flow rates selected in the present study cover the entire range of flow rate expected for dry weather and monsoon. The simulation is capable of differentiating between 2D and 3D modeling of particle trajectories, the effects of flow rate and trap geometry on flow patterns developed in the trap. The sediment retention ratio for 2D is higher than that for 3D modeling for all flow conditions, particle types and model geometry due to inclusion of lateral effects in 3D modeling. The invert trap having rectangular shape with trapezoidal base is found to be the most efficient configuration in both 2D and 3D modeling. 相似文献
106.
Jason D. Ehrick Matthew R. Luckett Santoshkumar Khatwani Yinan Wei Sapna K. Deo Leonidas G. Bachas Sylvia Daunert 《Macromolecular bioscience》2009,9(9):864-868
Stimuli‐responsive materials capable of manifesting physical changes in response to environmental signals are valuable tools for use in a variety of biomedical applications. Herein we describe one such smart glucose‐responsive hydrogel material prepared by immobilizing the glucose/galactose binding protein within an acrylamide hydrogel network. This hydrogel demonstrates a quantitative “accordion”‐like dynamic response in the presence of glucose. We further show the feasibility of employing this responsive smart material as a gating agent for controlled drug delivery, thus, demonstrating that these hydrogels may eventually lead to the development of implantable drug delivery systems for diabetes management applications.
107.
A simple, rapid, and precise reversed-phase liquid chromatographic method has been developed for the simultaneous determination of metformin in combination with glimepride. Under the developed conditions, good separation of the analytes was achieved in short analysis time. Several parameters affecting the separation of the analytes were studied, including pH and the concentration of SDS. The method is validated and shown to be linear in the range of 25 microg/mL to 150 microg/mL for metformin and 0.1 microg/mL to 0.6 microg/mL for glimepride. The method is applied for the analysis of these analytes in commercially available tablets. 相似文献
108.
A simple analytical two-body potential φ(r) = −Ar
−n + B exp(−pr
m) is considered for P-V calculations in bcc metals using Born stability criteria. It is shown that the stability of bcc metals
can be expressed uniquely as a function of a parameter q (discussed in the text). The P-V calculations are done in ten bcc metals. The calculations are compared with the experimental
data of shock-wave measurements and also with other potential available. It is found out that the present potential is better
than the other two-body potentials in case of bcc metals. Further, the calculations done for TOEC and the first pressure derivative
of SOEC are found in good agreement with the reported results. 相似文献
109.
110.
Summary Morpholine complexes of copper(II) alkanoates and chloroacetates of formula Cu(O2CR)2(Morph)n (where R = H, Me, Et, n-Pr, i-Pr, n-Bu, i-Bu, CH2Cl, CHCl2 and CCl3; Morph = Morpholine and n=1 and/or 2) have been isolated by the direct interaction of morpholine with the respective copper(II) carboxylates in a suitable organic medium and characterized by elemental analyses and various physicochemical techniques. Molecular weight determinations show that 11 complexes are dimeric whereas 21 complexes are monomeric in solution. Electronic spectra and magnetic moments suggest that 11 complexes are dinuclear carboxylate bridged species while 21 addition complexes have atrans-octahedral configuration. The i.r. spectra indicate that morpholine behaves as a monodentate ligand and coordinates through its nitrogen atom. 相似文献