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341.
Alberto N. Araujo Shiao Jun Jose L. F. C. Lima Julian Alonso Manel Poch Manel del Valle 《高等学校化学研究》1994,10(1):5-15
SimultaneousBiparametricDeterminationofTotalCalciumandPotassiuminBiologicalFluidsbyFlowInjectionAnalysis──UseofPowell'sMethod... 相似文献
342.
Correia J. G. Haas H. Araujo J. P. Marques J. G. Soares J. C. Melo A. A. 《Hyperfine Interactions》2001,136(3-8):155-159
Conversion electron-gamma PAC measurements of the 49–37 keV cascade in 80Br through the intermediate 2− state with T
1/2=7.4 ns were performed with a system of two magnetic lens spectrometers and two BaF2 scintillation detectors. The parent 80mBr activity with a halflife of 4.4 hrs was implanted into Ni, Zn and graphite at the ISOLDE separator at CERN. The observed
interaction frequency in the nickel matrix is in good agreement with the known value of the hyperfine field for Br in Ni and
the magnetic moment of the 2− state. From the measured quadrupole interaction in Zn and graphite the electric field gradients at Br were obtained.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
343.
Oscar A. Lenis-Rojas Sandra Cordeiro Marta Horta-Meireles Jhonathan Angel Araujo Fernndez Sabela Fernndez Vila Juan Andrs Rubiolo Pablo Cabezas-Sainz Laura Sanchez Alexandra R. Fernandes Beatriz Royo 《Molecules (Basel, Switzerland)》2021,26(18)
Cisplatin and its derivatives are commonly used in chemotherapeutic treatments of cancer, even though they suffer from many toxic side effects. The problems that emerge from the use of these metal compounds led to the search for new complexes capable to overcome the toxic side effects. Here, we report the evaluation of the antiproliferative activity of Fe(II) cyclopentadienyl complexes bearing n-heterocyclic carbene ligands in tumour cells and their in vivo toxicological profile. The in vitro antiproliferative assays demonstrated that complex Fe1 displays the highest cytotoxic activity both in human colorectal carcinoma cells (HCT116) and ovarian carcinoma cells (A2780) with IC50 values in the low micromolar range. The antiproliferative effect of Fe1 was even higher than cisplatin. Interestingly, Fe1 showed low in vivo toxicity, and in vivo analyses of Fe1 and Fe2 compounds using colorectal HCT116 zebrafish xenograft showed that both reduce the proliferation of human HCT116 colorectal cancer cells in vivo. 相似文献
344.
Mathematische Zeitschrift - We prove existence of equilibrium states with special properties for a class of distance expanding local homeomorphisms on compact metric spaces and continuous... 相似文献
345.
Aquino Carolina B. Silva João M. R. Oliveira Marcos H. R. Coriolano Ana C. F. Delgado Regina C. O. B. Fernandes Valter J. Araujo Antonio S. 《Journal of Thermal Analysis and Calorimetry》2019,136(5):2139-2144
Journal of Thermal Analysis and Calorimetry - Thermogravimetry was used in order to evaluate thermal and catalytic degradation of atmospheric residue of petroleum (ATR) which is found at Brazilian... 相似文献
346.
In this paper it is proved that the index of a Fredholm operator between $p$-adic Banach spaces is preserved under compact perturbations. A case of special interest is provided when the ground field is nonspherically complete. In this case the classical techniques are no longer valid and the relation between the kernels of a Fredholm operator and that of a small compact perturbation turn out to be in general much richer than in the complex context. 相似文献
347.
Fernandes V. J. Araujo A. S. Medeiros R. A. Matos J. R. Mercuri L. P. Silva A. O. Melo D. M. A. 《Journal of Thermal Analysis and Calorimetry》1999,56(3):1279-1282
High-density polyethylene (PE) was subjected to thermal degradation alone and in the presence of an ammonium-exchanged zeolite
chabazite (CHA/PE). The processes were carried out in a reactor connected online to a gas chromatograph/mass spectrometer
in order to analyse the evolved products. Polymer degradation was also evaluated by thermogravimetry, from room temperature
up to 800°C, under a dynamic nitrogen atmosphere, with multiple heating rates. From the TG curves, the activation energy relating
to the degradation process was calculated by using the Flynn and Wall multiple heating rate kinetic model for pure PE and
for CHA/PE. The exchanged chabazite exhibited good selectivity for the catalytic degradation of PE to low molecular mass hydrocarbons.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
348.
A finite element method for the axisymmetric three‐field Stokes system with a discontinuous pressure
J. H. Carneiro de Araujo V. Ruas 《Numerical Methods for Partial Differential Equations》1999,15(6):739-763
A quadrilateral based velocity‐pressure‐extrastress tensor mixed finite element method for solving the three‐field Stokes system in the axisymmetric case is studied. The method derived from Fortin's Q2 − P1 velocity‐pressure element is to be used in connection with the standard Galerkin formulation. This makes it particularly suitable for the numerical simulation of viscoelastic flow. It is proven to be second‐order convergent in the natural weighted Sobolev norms, for the system under consideration. The crucial result that the method is uniformly stable is proven for the case of rectangular meshes. © 1999 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 15: 739–763, 1999 相似文献
349.
Motivated by a problem in computer architecture we introduce a notion of the perfect distance-dominating set (PDDS) in a graph. PDDSs constitute a generalization of perfect Lee codes, diameter perfect codes, as well as other codes and dominating sets. In this paper we initiate a systematic study of PDDSs. PDDSs related to the application will be constructed and the non-existence of some PDDSs will be shown. In addition, an extension of the long-standing Golomb–Welch conjecture, in terms of PDDS, will be stated. We note that all constructed PDDSs are lattice-like which is a very important feature from the practical point of view as in this case decoding algorithms tend to be much simpler. 相似文献
350.