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91.
This article presents the changes in the thermal properties of the control and titanium dioxide (TiO2), both nano and bulk exposed Zebrafish bones by using thermo analytical techniques. The result shows that the mass loss due to the thermal decomposition occurs in three distinct steps due to loss of water, organic and inorganic materials. The titanium dioxide exposed bones present a different thermal behaviour compared to the control bones. The residue masses are found to be increased due to titanium dioxide exposure. In particular, nano titanium dioxide exposure increases the residue mass level significantly (three fold) when compared to titanium dioxide bulk exposure. These thermal characteristics can be used as a qualitative method to check the metal oxide intoxication in biological samples.  相似文献   
92.
93.
There are significant differences between the atomic orbital energies listed in the evaluated photon data library EPDL97 and values published elsewhere. In particular, comparisons with the values adopted by the National Institute of Standards and Technology (NIST) show discrepancies up to several hundred electron volts. Although the uncertainties in the EPDL97 atomic orbital energies were recognised by the original authors, the library has subsequently been widely adopted as a primary source of photon transport and atomic relaxation data. We compare experimentally measured X‐ray fluorescence spectra with fits using the EPDL97 and NIST line energies. Our results strongly favour the NIST energies for K‐shell and L‐shell fluorescent X‐rays and show that the EPDL97 atomic orbital energy values should not be used for applications, such as X‐ray fluorescence, where atomic relaxation phenomena are important. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
94.
We compare the results of small angle neutron scattering on the flux line lattice (FLL) obtained in the borocarbide superconductor LuNi2B2C with the applied field along the c- and a-axes. For H‖c the temperature dependence of the FLL structural phase transition from square to hexagonal symmetry was investigated. Above 10 K the transition onset field. H 2(T), rises sharply, bending away from H c2(T) in contradiction to theoretical predictions of the two merging. For H‖a a first order FLL reorientation transition is observed at H tr=3–3.5 kOe. Below H tr the FLL nearest neighbor direction is parallel to the b-axis, and above H tr to the c-axis. This transition cannot be explained using nonlocal corrections to the London model.  相似文献   
95.
Journal of Radioanalytical and Nuclear Chemistry - Analysis of irradiated material shortly after irradiation can be non-trivial due to highly radioactive activation and fission isotopes increasing...  相似文献   
96.
The construction of upper and lower bounds to the bilinear quantity g0, f, where f is the solution of an operator equation Tf = f0, requires either an approximation for f or one for T?1. In this paper the question of “best” approximation of T?1 by an operator of the form B = βI, where β is a real constant, is investigated for linear operators that are either self-adjoint or can be related by suitable manipulations to others that are. Particular attention is paid to a special operator, previously studied by Robinson, of importance in predicting the dynamic polarisabilities of quantum-mechanical systems.  相似文献   
97.
The hydrolysis of proteins   总被引:1,自引:0,他引:1  
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98.
The problem of scattering by an obstacle inR 3, the index of refraction of which differs from the index of refraction of free space, is examined. The problem reduces to an integral equation in the region defined by the obstacle. A scheme is proposed for regularizing the derived integral equation which ensures convergence of the iteration procedure.Published in Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Institute im. V. A. Steklova AN SSSR, Vol. 195, pp. 113–137, 1991.  相似文献   
99.
100.
The effect of flow shear on turbulent transport in tokamaks is studied numerically in the experimentally relevant limit of zero magnetic shear. It is found that the plasma is linearly stable for all nonzero flow shear values, but that subcritical turbulence can be sustained nonlinearly at a wide range of temperature gradients. Flow shear increases the nonlinear temperature gradient threshold for turbulence but also increases the sensitivity of the heat flux to changes in the temperature gradient, except over a small range near the threshold where the sensitivity is decreased. A bifurcation in the equilibrium gradients is found: for a given input of heat, it is possible, by varying the applied torque, to trigger a transition to significantly higher temperature and flow gradients.  相似文献   
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