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排序方式: 共有238条查询结果,搜索用时 31 毫秒
201.
Nguyen Hoa Hong A. T. Raghavender O. Ciftja M.-H. Phan K. Stojak H. Srikanth Yin Hua Zhang 《Applied Physics A: Materials Science & Processing》2013,112(2):323-327
Normally, CoFe2O4 has been known as ferromagnetic ferrite with a quite large magnetic moment. However, since we aim to inject the particles into the human body, we are also interested in ZnFe2O4 because in the human body, Fe and Zn exist, so that adding ZnFe2O4 is safer. In both cases, the nanoparticles are coated by silica in order to get rid of toxicity. Our main purpose is to test whether these nanoparticles affect the contractile function of heart cells. Our results on rat’s heart cells have shown that both Zn and Co ferrites improved the contractility of heart cells. Notably, although both nanoparticles increased contraction and delayed relaxation, Co ferrites induced a greater contraction but with a slower relaxation. We can theoretically argue that the magnetization effects of the quantum dots have a considerable effect on the pulsating properties of the heart cells. Through this effect, the locally applied magnetic field is able to induce as well as turn on/off various regular beating patterns, thus, resetting the heart beatings. 相似文献
202.
203.
M. Cuesta D.G. de Figueiredo P.N. Srikanth 《Calculus of Variations and Partial Differential Equations》2003,17(3):221-233
We start by discussing the solvability of the following superlinear problem where , is a smooth bounded domain and f satisfies a one-sided Landesman-Lazer condition. We also consider systems of semilinear elliptic equations with nonlinearities
of the above form, so exhibiting superlinearity as and resonance as . A priori bounds for the solutions of the equation and the system are obtained by using Hardy-type inequalities . Existence
of solutions is then obtained using topological degree arguments.
Received: 18 March 2002 / Accepted: 8 May 2002 / Published online: 5 September 2002 相似文献
204.
Goong Chen Tingwen Huang Maria Christina Mariani Roza Espandeary Rym Kanes Mohammed Sheriff Srikanth Srinivasan 《Physica A》2013
The Fourier spectrum of a curve on a given interval, as represented by the Fourier series, is very reflective of the oscillatory behavior of the curve as the “weights” of the Fourier coefficients can indicate the individual prominence of frequencies of oscillations. But, unfortunately, the calculations of the Fourier coefficients can often get quite cumbersome. 相似文献
205.
206.
A detailed study of point contact tunnelling into ceramic YBCO with electrochemically etched tips of Pt, Nb and W is reported.
The superconducting gap parameter (Δ) has been extracted fromI —V and dI/dV —V curves using various procedures. Our results indicate a gap value of about 20 meV. We observe that the zero bias conductance
is strongly dependent on the junction resistance. The normal state conductance varies linearly with bias voltage and the conductance
curves are asymmetric with respect to polarity of the bias voltage. With contacts of very high junction resistance, we observe
G(0)/G(100 mV) has a value as low as 1/6. This may be the lowest value reported so far. 相似文献
207.
T. Srikanth Reddy 《Tetrahedron letters》2006,47(14):2341-2344
Primary alcohols undergo selective and efficient tetrahydropyranylation in the presence of a catalytic amount of La(NO3)3·6H2O under solvent-free conditions. 相似文献
208.
209.
Determination of (113)Cd chemical shift is of significant interest in NMR characterization of metal porphyrins, metal-histidine interactions, and other metal-ligand interactions in many bioinorganic complexes and metalloproteins. In this study, we present a detailed account of a number of quantum chemical investigations aimed at relating isotropic and anisotropic (113)Cd chemical shifts to the structure of several biologically relevant complexes with discrete and polymeric structures. Calculated and experimentally determined chemical shift values are compared to correlate the variation of the chemical shift values with the structural changes around the metal center. Our results infer that the density functional theory using the Sadlej basis set on the cadmium atom is a suitable method for estimating cadmium shielding values to a reasonable accuracy. 相似文献
210.
Ahmed Kamal M. Naseer A. Khan K. Srinivasa Reddy Y.V.V. Srikanth T. Krishnaji 《Tetrahedron letters》2007,48(22):3813-3818
Aluminium triflate (0.01-0.1 mol %) was found to be an efficient catalyst for the acylation of alcohols, phenols, thiols and sugars with acetic anhydride in high yields under solvent-free conditions in a short reaction time at room temperature. Racemization of optically active alcohols and epimerization of sugars were not observed. The acylation efficacy of various acyl donors was also investigated. 相似文献