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51.
Olesya Myakonkaya Dr. Zhiyong Hu Muhammad Faizan Nazar Prof. Julian Eastoe 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(39):11784-11790
The stability and separation of colloids and nanoparticles has been addressed in numerous studies. Most of the work reported to date requires high cost, energy intensive approaches such as ultracentrifugation and solvent evaporation to recover the particles. At this point of time, when green science is beginning to make a real impact, it is vital to achieve efficient and effective separation and recovery of colloids to provide environmental and economic benefits. This article explores recent advances in strategies for recycling and reusing functional nanomaterials, which indicate new directions in lean engineering of high‐value nanoparticles, such as Au and Pd. 相似文献
52.
Afzal Shah Muhammad Zaheer Rumana Qureshi Zareen Akhter Muhammad Faizan Nazar 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):1082-1087
Cyclic voltammetry (CV) coupled with UV–vis and fluorescence spectroscopy were used to probe the interaction of potential anticancer drug, 4-nitrophenylferrocene (NFC) with DNA. The electrostatic interaction of the positively charged NFC with the anionic phosphate of DNA was evidenced by the findings like negative formal potential shift in CV, ionic strength effect, smaller bathochromic shift in UV–vis spectroscopy, incomplete quenching in the emission spectra and decrease in viscosity. The diffusion coefficients of the free and DNA bound forms of the drug were evaluated from Randles–Sevcik equation. The binding parameters like binding constant, ratio of binding constants (Kred/Kox), binding site size and binding free energy were determined from voltammetric data. The binding constant was also determined from UV–vis and fluorescence spectroscopy with a value quite close to that obtained from CV. 相似文献
53.
54.
Hans Matter Dr. Marc Nazaré Dr. Stefan Güssregen Dr. David W. Will Dr. Herman Schreuder Dr. Armin Bauer Dr. Matthias Urmann Dr. Kurt Ritter Dr. Michael Wagner Dr. Volkmar Wehner Dr. 《Angewandte Chemie (International ed. in English)》2009,48(16):2911-2916
Attractive chlorine : Noncovalent interactions between chlorine or bromine atoms and aromatic rings in proteins open up a new method for the manipulation of molecular recognition. Substitution at distinct positions of two factor Xa inhibitors improves the free energy of binding by interaction with a tyrosine unit. The generality of this motif was underscored by multiple crystal structures as well as high‐level quantum chemical calculations (see picture).
55.
Anuar Ishak Roslinda Nazar Ioan Pop 《Communications in Nonlinear Science & Numerical Simulation》2009,14(1):109-118
The steady laminar magnetohydrodynamic (MHD) boundary-layer flow past a wedge with constant surface heat flux immersed in an incompressible micropolar fluid in the presence of a variable magnetic field is investigated in this paper. The governing partial differential equations are transformed into a system of ordinary differential equations using similarity variables, and then they are solved numerically by means of an implicit finite-difference scheme known as the Keller-box method. Numerical results show that micropolar fluids display drag reduction and consequently reduce the heat transfer rate at the surface, compared to the Newtonian fluids. The opposite trends are observed for the effects of the magnetic field on the fluid flow and heat transfer characteristics. 相似文献
56.
A.K. Alomari M.S.M. Noorani R. Nazar 《Communications in Nonlinear Science & Numerical Simulation》2009,14(4):1196-1207
In this paper, by means of the homotopy analysis method (HAM), the solutions of some Schrodinger equations are exactly obtained in the form of convergent Taylor series. The HAM contains the auxiliary parameter ?, that provides a convenient way of controlling the convergent region of series solutions. This analytical method is employed to solve linear and nonlinear examples to obtain the exact solutions. HAM is a powerful and easy-to-use analytic tool for nonlinear problems. 相似文献
57.
Let U be a bounded open subset of ?d, d ≥ 2 and f ∈ C(?U). The Dirichlet solution fCU of the Dirichlet problem associated with the Laplace equation with a boundary condition f is not continuous on the closure ū of U in general if U is not regular but it is always Baire-one.Let H(U) be the space of all functions continuous on the closure ū and harmonic on U and F(H(U)) be the space of uniformly bounded absolutely convergent series of functions in H(U). We prove that fCU can be obtained as a uniform limit of a sequence of functions in F(H(U)). Thus fCU belongs to the subclass B1/2 of Baire-one functions studied for example in [8]. This is not only an improvement of the result obtained in [10] but it also shows that the Dirichlet solution on the closure ū can share better properties than to be only a Baire-one function. Moreover, our proof is more elementary than that in [10].A generalization to the abstract context of simplicial function space on a metrizable compact space is provided.We conclude the paper with a brief discussion on the solvability of the abstract Dirichlet problem with a boundary condition belonging to the space of differences of bounded semicontinuous functions complementing the results obtained in [17]. 相似文献
58.
Stability and convergence of the spectral Lagrange-Galerkin method for mixed periodic/non-periodic convection-dominated diffusion problems 总被引:1,自引:0,他引:1
We present a convergence analysis of the spectral Lagrange-Galerkinmethod for mixed periodic/non-periodic convection-diffusionproblems. The scheme is unconditionally stable, independentof the diffusion coefficient, even in the case when numericalquadrature is used. The theoretical predictions are illustratedby a series of numerical experiments. For the periodic case,our results present a significant improvement on those givenby Süli & Ware (1991) SIAM J. Numer.Anal.28, 423-445). 相似文献
59.
Zafar M. N. Nazar M. F. Raza M. A. Mughal E. U. Dalebrook A. F. Wright L. J. 《Russian Journal of General Chemistry》2017,87(3):554-563
Russian Journal of General Chemistry - Bis(pyridinium)amine 4,4'-[(2-aminophenyl)azanediyl]bis(1-methylpyridin-1-ium)triflate ([H2L][TfO]2) was synthesized and characterized by elemental... 相似文献
60.
Charge ordering in lithium vanadium phosphates: electrode materials for lithium-ion batteries 总被引:2,自引:0,他引:2
Yin SC Grondey H Strobel P Huang H Nazar LF 《Journal of the American Chemical Society》2003,125(2):326-327
The delithiation process in monoclinic Li3V2(PO4)3 has been determined by powder neutron diffraction coupled with 7Li solid-state NMR techniques. Charge ordering of vanadium (V3+/V4+) was observed in Li2V2(PO4)3 as shown by the gray and blue V-O octahedra, respectively, indicating that the electrons are pinned in this phase and hence transport is limited. 相似文献