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121.
Geraldo L. Crossetti Marcos L. Dias Bruno T. Queiroz Luciana P. Silva Cludio M. Ziglio Joo A. S. Bomfim Carlos A. L. Filgueiras 《应用有机金属化学》2004,18(7):331-336
Three isothiocyanate complexes of nickel(II) containing diimine [ArN?C(Me)? C(Me)?NAr]Ni‐ (NCS)2 (1), iminophosphine [Ph2PC6H4CH?NAr]Ni(NCS)2 (2), or diphosphine (dppe)Ni(NCS)2 (3), [Ar = 2, 6‐iPr‐C6H3; dppe = 1, 2‐bis(diphenylphosphine)ethane] were synthesized and examined for ethylene polymerization activated by methylaluminoxane (MAO). Their behavior was compared with those of the corresponding halide analogues [ArN?C(Me)? C(Me)?NAr]NiBr2 (4), [Ph2PC6H4CH?NAr]NiBr2 (5), and (dppe)NiCl2 (6). The diimines showed the highest polymerization activity. Replacement of the halide for the NCS pseudo halide affected the activity and decreased the molecular weight of the polymer formed. The highest molecular weights were obtained with the diimine complexes. Highly branched polyethylenes were obtained with the bulkier complexes 1 and 4. Replacement of the halide for NCS in the diimine complexes also caused an increase in the branching content, whereas the opposite occurs for the iminophosphine complexes. The different activities and behavior of the catalyst systems with halide versus NCS in the polymerization of ethylene and the characteristics of the final products suggest a modification in the active species caused by the non‐chelating ligand. Polymer molecular weight and branching content is dependent on the MAO/Ni molar ratio and on the working temperature. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
122.
We prove that, like in the linear case, there is a canonical prototype of a p-dominated homogeneous polynomial through which every p-dominated polynomial between Banach spaces factors. 相似文献
123.
124.
Geraldo Botelho 《Indagationes Mathematicae》2005,16(2):157-169
In this paper we introduce two properties for ideals of polynomials between Banach spaces and showhow useful they are to deal with several a priori different problems. By investigating these properties we obtain, among other results, new polynomial characterizations of L∞ spaces and characterizations of Banach spaces whose duals are isomorphic to f 1 (Λ). 相似文献
125.
Soraia Lúcia da Silva Mauro Nacif Rocha Geraldo Robson Mateus 《Annals of Operations Research》2002,116(1-4):57-68
The traffic generation models, which describe how the clients use the network services, as well as the mobility models, which describe how clients move within the service area covered by the network, are essential tools for QoS analysis in these environments. In this paper we present the simulation of a new mobility model implemented for the analysis of QoS parameters of a mobile network, such as channel occupation time, handoff and new call blocking probabilities. 相似文献
126.
Geraldo?Botelho Jamilson?R.?CamposEmail authorView authors OrcID profile 《Monatshefte für Mathematik》2017,183(3):415-435
In this paper we provide a unifying approach to the study of Banach ideals of linear and multilinear operators defined, or characterized, by the transformation of vector-valued sequences. We also investigate the linear and multilinear stabilities of some frequently used classes of vector-valued sequences. Concrete applications are provided. 相似文献
127.
H. Beirão da Veiga 《Journal of Mathematical Fluid Mechanics》2014,16(3):539-550
In this notes we consider the stationary Stokes system in a bounded, connected, three-dimensional smooth domain, with homogeneous Dirichlet boundary condition. Proofs also apply to the n-dimensional case, and to other boundary conditions, like Navier-slip ones. We say here that a solution is classical if all derivatives appearing in the equations are continuous up to the boundary. It is well known, for long time, that solutions of the Stokes system are classical if the external forces belong to the H?lder space \({C^{0,\; \lambda}(\bar{\Omega})}\) . It is also well known that, in general, solutions are not classical in the presence of continuous external forces. Hence, a very challenging problem is to find Banach spaces, strictly containing the H?lder spaces \({C^{0,\; \lambda}(\bar{\Omega})}\) such that solutions to the Stokes problem corresponding to forces in the above space are classical. We prove this result for external forces in a suitable functional space, denoted \({{\rm C}_*(\bar{\Omega})}\) , introduced in references Beirão da Veiga (On the solutions in the large of the two-dimensional flow of a non-viscous incompressible fluid, 1982) and Beirão da Veiga (J Differ Equ 54(3):373–389, 1984) in connection with the Euler equations. 相似文献
128.
Hugo Beir?o da Veiga Petr Kaplicky Michael R??i?ka 《Journal of Mathematical Fluid Mechanics》2011,13(3):387-404
This article is concerned with the global regularity of weak solutions to systems describing the flow of shear thickening
fluids under the homogeneous Dirichlet boundary condition. The extra stress tensor is given by a power law ansatz with shear
exponent p≥ 2. We show that, if the data of the problem are smooth enough, the solution u of the steady generalized Stokes problem belongs to W1,(np+2-p)/(n-2)(W){W^{1,(np+2-p)/(n-2)}(\Omega)} . We use the method of tangential translations and reconstruct the regularity in the normal direction from the system, together
with anisotropic embedding theorem. Corresponding results for the steady and unsteady generalized Navier–Stokes problem are
also formulated. 相似文献
129.
Oscar Blasco Geraldo Botelho Daniel Pellegrino Pilar Rueda 《Monatshefte für Mathematik》2011,163(2):131-147
In this paper we prove new results concerning summability properties of multilinear mappings between Banach spaces, such as an extension of Littlewood’s 4/3 Theorem. The role of the Littlewood–Orlicz property in the theory is established, especially in the question of determining when multilinear mappings are (1; 2, . . . , 2)-summing. 相似文献
130.
Ramos-Jesus J Carvalho KA Fonseca RA Oliveira GG Melo SM Alcântara-Neves NM Dutra RF 《Analytical and bioanalytical chemistry》2011,401(3):917-925
The American visceral leishmaniasis is an important cause of morbidity and mortality in Brazil for both humans and dogs. Attempts
to make a diagnosis of this disease need to be improved, especially in endemic areas, and in the tracking and screening of
asymptomatic dogs, which are their main host in urban areas. A quartz crystal microbalance immunosensor for the diagnosis
of the canine visceral leishmaniasis using a recombinant antigen of Leishmania chagasi (rLci2B-NH6) was developed. The rLci2B-NH6 was tightly immobilized on a quartz crystal gold electrode by self-assembled monolayer
based on short-chain length thiol. The strategy was the use of the antigen-histidine tail covalently linked to glutaraldehyde
performing a Schift base which permits a major exposure of epitopes and a reduced steric hindrance. The immunosensor showed
good results regarding sensitivity and reproducibility, being able to distinguish positive and negative canine serum for L. chagasi. Furthermore, the immunosensor can be reused through exposure to sodium dodecyl sulfate solution, which promotes the dissociation
of antigen–antibody binding, restoring the sensor surface with immobilized biologically active antigens for further analysis. 相似文献