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171.
172.
Fluorescence properties of four based derivatives [An] (where n = 1–4) and their Cu(II) heterochelates of the type [Cu(An)(CQ)(OH)]?xH2O {where A1 = 3‐(2‐oxo‐2H‐chromen‐3‐yl)‐4H‐furo[3,2‐c]chromen‐4‐one, A2 = 8‐methyl‐3‐(2‐oxo‐2H‐chromen‐3‐yl)‐4H‐furo[3,2‐c]chromen‐4‐one, A3 = 6‐methyl‐3‐(2‐oxo‐2H‐chromen‐3‐yl)‐4H‐furo[3,2‐c]chromen‐4‐one, A4 = 8‐chloro‐3‐(2‐oxo‐2H‐chromen‐3‐yl)‐4H‐furo[3,2‐c]chromen‐4‐one and x = 3, 2, 4, 1} were studied at room temperature. The fluorescence spectra of heterochelates show red shift, which may be due to the chelation by the ligands to the metal ion. It enhances ligand ability to accept electrons and decreases the electron transition energy. The kinetic parameters such as order of reaction (n), energy of activation (Ea), entropy (ΔS#), pre‐exponential factor (A), enthalpy (ΔH#) and Gibbs free energy (ΔG#) have been reported. The antimicrobial activity of Clioquinol and Cu(II) heterochelates have been determined and described. All the heterochelates showed a more effective antimicrobial activity than the free ligand. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
173.
JPC – Journal of Planar Chromatography – Modern TLC - Adensitometric HPTLC method has been established for analysis in alcohol extracts of the seeds and leaves of Achyranthes aspera L.... 相似文献
174.
We discuss recent observations of the heat capacity and magnetization of a fluid 3He monolayer adsorbed on graphite plated with a bilayer of HD. Approaching the density at which the monolayer solidifies into a
commensurate solid, we observe an apparent divergence of the effective mass. However, the inferred values of F0a tend to a constant. We interpret this in terms of a Mott–Hubbard transition between a 2D Fermi liquid and a magnetically disordered solid occurring via the Brinkman–Rice–Anderson–Vollhardt scenario. 相似文献
175.
M. Chawda N. Patel K. C. Sebastian D. R. S. Somayajulu M. Sarkar R. P. Singh 《辐射效应与固体损伤》2013,168(6):361-364
Radiation-induced defects are studied in cubic rhodium metal, using the local probe technique ‘Time differential perturbed angular correlation’ (TDPAC) at liquid N2 temperature. Isochronal annealing was done at 300, 1073 and 1473 K temperatures. The irradiated sample showed two quadrupole interaction frequencies at 1150 and 93 MHz. The low frequency disappeared at room-temperature annealing, which was assigned to In trapped at a vacancy, whereas the higher frequency remained up to high temperatures and was attributed to In trapped at Rh–C complexes in the Rh matrix. 相似文献
176.
Himatkumar V. Patel Kavita A. Vyas Sudhanshu P. Pandey Peter S. Fernandes 《合成通讯》2013,43(21):3081-3087
A novel one-step synthesis of 4-arylazo-1H-1, 3, 5-trimethylpyrazoles is accomplished by reaction of N, N-dimethylhydrazine with 2, 3, 4-pentantrione-3-arylhydrazones via an unusual demethylation. 相似文献
177.
Vikas N. Telvekar Kavit N. Patel Harish S. Kundaikar Hemchandra K. Chaudhari 《Tetrahedron letters》2008,49(14):2213-2215
A simple and mild method for the conversion of varieties of aldehydes to the corresponding nitriles using aqueous ammonia and aqueous sodium dichloroiodate reagent at room temperature is discussed. Advantages of this system are short reaction time, easy work-up and moderate to good yields. 相似文献
178.
Ajit Patel Amiya K. Pani Neela Nataraj 《Numerical Methods for Partial Differential Equations》2008,24(6):1460-1484
In this article a standard mortar finite element method and a mortar element method with Lagrange multiplier are used for spatial discretization of a class of parabolic initial‐boundary value problems. Optimal error estimates in L∞(L2) and L∞(H1)‐norms for semidiscrete methods for both the cases are established. The key feature that we have adopted here is to introduce a modified elliptic projection. In the standard mortar element method, a completely discrete scheme using backward Euler scheme is discussed and optimal error estimates are derived. The results of numerical experiments support the theoretical results obtained in this article. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008 相似文献
179.
An operationally simple and high yielding procedure has been developed for the preparation of nitriles from aldoximes and primary amides using bromodimethylsulfonium bromide (BDMS) as a novel and efficient reagent in the absence of any added base or catalyst. The optimal protocol is applicable to access a wide range of cyano compounds including aromatic, heterocyclic, and aliphatic species. The conversion of aldoximes to nitriles takes place at room temperature in acetonitrile, whereas acetonitrile at reflux temperature is required for rapid conversion in the case of primary amides. 相似文献
180.
Raphaël Trouillon Zachary Combs Bhavik Anil Patel Danny O’Hare 《Electrochemistry communications》2009,11(7):1409-1413
Stability of sensors in biosamples is a critical issue and can be mitigated by membranes. The effect of different membranes (Nafion, cellulose acetate, chitosan, fibronectin, PSS/PL) on the electrochemistry of an outer-sphere redox couple (ruthenium II/III hexaammine) and on the electrocatalytic reduction of dissolved oxygen are described. Biofouling has been induced by albumin solutions. Results demonstrate good performances of fibronectin in all situations investigated. Other membranes do not provide a satisfactory protection from biofouling and some of them, PSS/PL in particular, seriously disturb electrochemical mechanisms. 相似文献