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41.
The molybdenum(VI)-peroxo complexes containing Mannich base ligands having a formula as [MoO(O2)2(L-L)] [where L-L=morpholinobenzyl benzamide (MBB), piperidinobenzyl benzamide (PBB), morpholinobenzyl urea (MBU), piperidinobenzyl urea (PBU), morpholinobenzyl thiourea (MBTU), piperdinobenzyl thiourea (PBTU)] have been synthesized and characterized by physico-chemical, electrochemical techniques and TGA/DTA studies. The complexes have been prepared by stirring ammonium molybdate and excess of 30% aqueous-H2O2 and then treatment with ethanolic solution of the ligand. Studies revealed that these complexes were non-electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode through carbonyl oxygen/thiocarbonyl sulphur and the ring nitrogen. The cyclic voltammograms of the complexes show two quasi-reversible steps involving complexes. The complexes have also been tested for antibacterial activity against Salmonella and Kleibsella. The antibacterial study of the ligands and complexes indicate that the complexes exhibit higher activity than the free ligands.  相似文献   
42.
We examine the role of space-time geometry in the non-adiabatic collapse of a star dissipating energy in the form of radial heat flow, studying its evolution under different initial conditions. The collapse of a star filled with a homogeneous perfect fluid is compared with that of a star filled with inhomogeneous imperfect fluid under anisotropic pressure. Both the configurations are spherically symmetric. However, in the latter case, the physical space t?=?constant of the configurations endowed with spheroidal or pseudospheroidal geometry is assumed to be inhomogeneous. It is observed that as long as the collapse is shear-free, its evolution depends only on the mass and size of the star at the onset of collapse.  相似文献   
43.
4- n -Nonyl-4-cyanobiphenyl, C22H27N, Mr= 305.45, triclinic, P 1, a=9.765(1)A, b= 11.460(2)A, c=17.860(2)A, alpha=85.460(2), beta=80.870(1), gamma=71.630(1) , V=1871.9(3)A3, Z= 4, Dm=1.079M g -3, Dc= 1.084 M g -3, mu=0.463 mm -1, F (000)=664, lambda (CuK alpha)=1.5418 A, final R and wR 2 are 0.0523 and 0.1559, respectively.  相似文献   
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45.
Numerical and analytical investigations of the thermosolutal instability in a viscoelastic Rivlin-Ericksen fluid are carried out in the presence of a uniform vertical magnetic field to include the Hall current with a uniform angular velocity in a porous medium. For stationary convection, the stable solute gradient parameter and the rotation have stabilizing effects on the system, whereas the magnetic field and the medium permeability have stabilizing or destabilizing effects on the system under certain conditions. The Hall current in the presence of rotation has stabilizing effects for sufficiently large Taylor numbers, whereas in the absence of rotation, the Hall current always has destabilizing effects. These effects have also been shown graphically. The viscoelastic effects disappear for stationary convection. The stable solute parameter, the rotation, the medium permeability, the magnetic field parameter, the Hall current, and the vis-coelasticity introduce oscillatory modes into the system, which are non-existent in their absence. The sufficient conditions for the non-existence of overstability are also obtained.  相似文献   
46.
In this work we explored strong field-induced decay of doubly excited transient Coulomb complex Ar ?? → Ar 2+ + 2e. We measured the correlated two-electron emission as a function of carrier envelop phase (CEP) of 6 fs pulses in the non-sequential double ionization (NSDI) of argon. Classical model calculations suggest that the intermediate doubly excited Coulomb complex loses memory of its formation dynamics. We estimated the ionization time difference between the two electrons from NSDI of argon and it is 200 ± 100 as (N Camus et al, Phys. Rev. Lett. 108, 073003 (2012)).  相似文献   
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The dynamics of indirectly coupled Lorenz circuits is investigated experimentally. The in-phase and anti-phase synchronization of indirectly coupled chaotic oscillators reported in Phys. Rev. E 81, 046216 (2010) is verified by physical experiments with electronic circuits. Two chaotic systems coupled through a common dynamic environment shows the verity of synchronization behaviours such as anti-phase synchronization, in-phase synchronization, identical synchronization, anti-synchronization, etc.  相似文献   
49.
B. D. SHARMA 《ChemInform》1987,18(20):no-no
On the basis of previously reported structural data it is suggested that the so-called crystalline polymorphs of P2O5 are in fact three distinct compounds with different structural characteristics but with the same empirical formula.  相似文献   
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