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Two polymer (polyethylene) reference materials have been produced in support of EC Directive 94/ 62/EC on plastic packaging and packaging material The paper describes the preparation of the materials, the analytical work performed to characterize their homogeneity and stability, and the certification of the materials for a range of elements. The technical and statistical evaluation of the results are also summarized. 相似文献
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Stéphanie Boissé Jutta Rieger Gaëlle Pembouong Patricia Beaunier Bernadette Charleux 《Journal of polymer science. Part A, Polymer chemistry》2011,49(15):3346-3354
Aqueous emulsion polymerizations of styrene were performed in the presence of a macromolecular reversible addition‐fragmentation chain transfer (RAFT) agent (macroRAFT) composed of acrylic acid (AA) and poly(ethylene oxide) methyl ether acrylate (PEOA), end‐capped by a reactive dodecyl trithiocarbonate group (P(AA‐co‐PEOA)‐TTC). The influence of the stirring speed or the presence of different amounts of a divalent salt, CaCl2, were investigated in this polymerization‐induced self‐assembly process, in which spherical and nonspherical nano‐objects were formed upon the synthesis of amphiphilic diblock copolymers in situ. It appeared that the addition of CaCl2 led to the controlled formation of different nano‐objects such as spheres, fibers or vesicles, whereas an appropriate stirring speed was required for the formation of nanofibers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
65.
Jeroen Suijs Peter Borm Herbert Hamers Marieke Quant Maurice Koster 《Annals of Operations Research》2005,137(1):117-140
This paper focuses on sharing the costs and revenues of maintaining a public network communication structure. Revenues are
assumed to be bilateral and communication links are publicly available but costly. It is assumed that agents are located at
the vertices of an undirected graph in which the edges represent all possible communication links. We take the approach from
cooperative game theory and focus on the corresponding network game in coalitional form which relates any coalition of agents
to its highest possible net benefit, i.e., the net benefit corresponding to an optimal operative network. Although finding
an optimal network in general is a difficult problem, it is shown that corresponding network games are (totally) balanced.
In the proof of this result a specific relaxation, duality and techniques of linear production games with committee control
play a role. Sufficient conditions for convexity of network games are derived. Possible extensions of the model and its results
are discussed.
The research of Jeroen Suijs has been made possible by a fellowship of the Royal Netherlands Academy of Arts and Sciences. 相似文献
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M. Pulido P. Borm R. Hendrickx N. Llorca J. Sánchez-Soriano 《Annals of Operations Research》2008,158(1):133-141
This paper deals with bankruptcy situations in which in addition to the claims, an exogenously given reference point for the
allocation of the estate is present. We introduce and analyse two types of compromise solutions and show that they coincide
with the τ value of two corresponding TU games. We apply our solutions to a real-life case of allocating university money to degree
courses.
Research supported by Generalitat Valenciana, through ACOMP06/040, ACOMP07/136 and GV05/189, and by the Government of Spain
and FEDER fund under project MTM2005-09184-C02-02. M. Pulido’s research is partially supported by Fundación Séneca of Comunidad
Autónoma de la Región de Murcia, through 02911/PI/05. Ruud Hendrickx author acknowledges financial support from the Netherlands
Organisation for Scientific Research (NWO). 相似文献
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