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971.
Eric A. Carlen Jos A. Carrillo Maria C. Carvalho 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2009,26(5):1675-1700
We show the propagation of regularity, uniformly in time, for the scaled solutions of the inelastic Maxwell model for small inelasticity. This result together with the weak convergence towards the homogeneous cooling state present in the literature implies the strong convergence in Sobolev norms and in the L1 norm towards it depending on the regularity of the initial data. The strategy of the proof is based on a precise control of the growth of the Fisher information for the inelastic Boltzmann equation. Moreover, as an application we obtain a bound in the L1 distance between the homogeneous cooling state and the corresponding Maxwellian distribution vanishing as the inelasticity goes to zero. 相似文献
972.
A. M. C. Arriaga J. Q. Lima J. N. Vasconcelos M. C. F. de Oliveira M. Andrade‐Neto G. M. P. Santiago D. E. A. Uchoa G. T. Malcher J. Mafezoli R. Braz‐Filho 《Magnetic resonance in chemistry : MRC》2009,47(6):537-540
1H and 13C NMR chemical shifts of praecansone B, pongaflavone and dehydrorotenone isolated from Tephrosia egregia Sandw and obovatin from T. toxicaria Pers. were unambiguously assigned by 1D and 2D NMR experiments including 1H, 1H COSY, gHMQC and gHMBC, allowing the correction of literature assignments.Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
973.
Rodrigo Leal de Paiva Carvalho Ernesto Cesar Pinto Leal‐Junior Maria Carla Petrellis Rodrigo Labat Marcos Maria Helena Catelli de Carvalho Gilberto De Nucci Rodrigo Alvaro Brandão Lopes‐Martins 《Photochemistry and photobiology》2013,89(2):508-512
Muscle injuries represent ca 30% of sports injuries and excessive stretching of muscle causes more than 90% of injuries. Currently the most used treatments are nonsteroidal anti‐inflammatory drugs (NSAIDs), however, in last years, low‐level laser therapy (LLLT) is becoming an interesting therapeutic modality. The aim of this study was to evaluate the effect of single and combined therapies (LLLT, topical application of diclofenac and intramuscular diclofenac) on functional and biochemical aspects in an experimental model of controlled muscle strain in rats. Muscle strain was induced by overloading tibialis anterior muscle of rats. Injured groups received either no treatment, or a single treatment with topical or intramuscular diclofenac (TD and ID), or LLLT (3 J, 810 nm, 100 mW) 1 h after injury. Walking track analysis was the functional outcome and biochemical analyses included mRNA expression of COX‐1 and COX‐2 and blood levels of prostaglandin E2 (PGE2). All treatments significantly decreased COX‐1 and COX‐2 gene expression compared with injury group (P < 0.05). However, LLLT showed better effects than TD and ID regarding PGE2 levels and walking track analysis (P < 0.05). We can conclude that LLLT has more efficacy than topical and intramuscular diclofenac in treatment of muscle strain injury in acute stage. 相似文献
974.
P.V. Trevizoli C.S. Alves M.A.B. Mendes A. Magnus G. Carvalho S. Gama 《Journal of magnetism and magnetic materials》2008
Magnetic refrigeration is an innovative technology owing to its high-efficiency, low-energy consumption, and environmental friendliness. However, the manufacturing process of the magnetocaloric materials is an obstacle to the effective application of those materials on refrigeration systems. In this work, we present a magnetic characterization of the Gd5.09Ge2.03Si1.88.alloy, analyzing the as-cast bulk and the sintered tablets after some heat treatments. The study of powder metallurgy parameters such as grain size, compacting pressure and sintering process has showed results comparable to the as-cast alloy, which presents ΔST=−18 /kg K. 相似文献
975.
A differential pulse polarographic method has been developed for the quantitative determination of niobium in pyrochlore ore. One-step polarographic curves were obtained in 0.01 mol L(-1) EDTA as supporting electrolyte. Analytical curves indicated that response was linearly dependent on Nb(V) concentration between 1.6 and 8.6 mg L(-1) in the pH range 2-5. The system is quasi-reversible and controlled by diffusion in 0.01 mol L(-1) EDTA as supporting electrolyte; the electrode process involves one-electron reduction of Nb(V) to Nb(IV). The results obtained so far for niobium in pyrochlore ore were comparable with those obtained by X-ray fluorescence determination. Ions such as Fe(III), Cr(III), As(III), Cu(II), Ni(II), Co(II), Mn(II), Sn(IV), Zn(II), V(V), Ta(V), W(VI), Ce(IV), and Ti(IV) did not interfere. Possible interference from Pb(II) can be avoided by complexation with the supporting electrolyte in the pH range 3.5 to 4.6; Mo(VI) ions can be tolerated when their concentration is one-tenth that of Nb(V). 相似文献
976.
We apply a method developed in our earlier work on a non-local phase kinetics equation to give a simple proof of the non-linear
stability of fronts for the Cahn–Hilliard equation.
Received: 14 November 2000 / Accepted: 30 July 2001 相似文献
977.
Eunice F. S. Vieira Antonio R. Cestari Wagner A. Carvalho Cíntia dos S. Oliveira Renata A. Chagas 《Journal of Thermal Analysis and Calorimetry》2012,109(3):1407-1412
Fish scale of the species Leporinus elongatus was tested as an adsorbent for anionic Remazol dyes. Characterization has suggested that hydroxyl, phosphate, amides I, II, and III, and carbonate groups are the potential sites of adsorption. From solution calorimetry, values of thermal effects, Q int, and amount of dye that interacts, n int, were determined. The adsorption order observed was Yellow-dye/scale?>?Red-dye/scale?>?Blue-dye/scale. The Q int and n int data were successfully adjusted to the Langmuir isotherm model. The dyes removals by fish scale are exothermic processes (from ?83 to ?199?kJ?mol?1) with negative entropies and are thermodynamically spontaneous. The thermodynamic results suggest that the interactions at scale/anionic dye interfaces occur mainly by surface reactions. It was finding that fish scale is a new and suitable sorbent material for recovery and biosorption/adsorption of anionic dyes from aqueous solutions. 相似文献
978.
Esdras Penêdo de Carvalho Ansio dos Santos Júnior To Fu Ma 《Applied mathematics and computation》2008,200(2):529
A new approach for solving the optimal power flow (OPF) problem is established by combining the reduced gradient method and the augmented Lagrangian method with barriers and exploring specific characteristics of the relations between the variables of the OPF problem. Computer simulations on IEEE 14-bus and IEEE 30-bus test systems illustrate the method. 相似文献
979.
D.M. Souza A.L. Andrade J.D. Fabris P. Valério A.M. Góes M.F. Leite R.Z. Domingues 《Journal of Non》2008,354(42-44):4894-4897
Magnetic iron oxide nanoparticles properly coated with silica may be interesting in molecular biology, particularly as an auxiliary diagnostic material in biomedicine. This paper describes the coating of superparamagnetic magnetite nanoparticles with amorphous silica by sol–gel process using tetraethoxysilane. The physical–chemical characterization of the magnetite powder before and after silica-coating was performed by X-ray diffraction, Fourier-transform infrared, and zeta potential. The in vitro biocompatibility of the samples was analyzed by the viability/proliferation and collagen secretion capability of incubated osteoblasts in the presence of the composites. In summary, it was demonstrated that osteoblast viability decreased to about 20% in the presence of silica-coated magnetite nanoparticles when compared to the control group result. Moreover, the silica-coated magnetite nanoparticles did not alter osteoblast collagen secretion. The in vitro preliminary evaluation showed that silica-coating magnetite nanoparticles did not produce any severe alteration in biocompatibility. Further investigations are required to better understand the biocompatibility of silica-coated magnetite nanoparticles in biomedical applications. 相似文献
980.
We survey results concerning automatic structures for semigroup constructions, providing references and describing the corresponding
automatic structures. The constructions we consider are: free products, direct products, Rees matrix semigroups, Bruck-Reilly
extensions and wreath products. 相似文献