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31.
Vasilios Kotzabasakis Konstantinos Kostakis Marinos Pitsikalis Nikos Hadjichristidis David J. Lohse Thomas Mavromoustakos Constantinos Potamitis 《Journal of polymer science. Part A, Polymer chemistry》2009,47(17):4314-4325
The Cs‐symmetry hafnium metallocene [(p‐Et3Si)C6H4]2C(2,7‐di‐tert‐BuFlu)(C5H4)Hf(CH3)2 and tetrakis(pentafluorophenyl) borate dimethylanilinium salt ([B(C6F5)4]?[Me2NHPh]+) were used as the catalytic system for the polymerization of higher α‐olefins (from hexene‐1 to hexadecene‐1) in toluene at 0 °C. The evolution of the polymerization was studied regarding the variation of the molecular weight, molecular weight distribution and yield with time. The effect of the monomer structure on the polymerization kinetics was established. The role of trioctylaluminum in accelerating the polymerization was investigated. 13C NMR spectroscopy was used to study the microstructure of the poly(α‐olefins) by the determination of the pentad monomer sequences. The thermal properties of the polymers were obtained by differential scanning calorimetry, DSC. The results were discussed in connection with the polymer microstructure. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4314–4325, 2009 相似文献
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Constantina Papatriantafyllopoulou Marta Estrader Constantinos G. Efthymiou Despina Dermitzaki Konstantinos Gkotsis Aris Terzis Carmen Diaz Spyros P. Perlepes 《Polyhedron》2009,28(9-10):1652-1655
Employing the mononuclear complex [Ni{(py)C(Me)NO}2{(py)C(Me)NOH}] (1) as ‘ligand’ [(py)C(Me)NOH = methyl 2-pyridyl ketone oxime], the use of the ‘metal complexes as ligands’ approach has led to the synthesis of the mixed NiII/LnIII complexes [NiTb{(py)C(Me)NO}2(NO3)3{(py)C(Me)NOH}] (2), [Ni2Ln2{(py)C(Me)NO}6(NO3)4] (Ln = Dy, 3; Ln = Tb, 4) and [Ni2Tb{(py)C(Me)NO}6](NO3) (5). The structures of 2, 3, and 5, and the magnetic properties of 2 and 5 are briefly discussed. 相似文献
33.
A tree T is said to be homogeneous if it is uniquely rooted and there exists an integer b ≥ 2, called the branching number of T, such that every t ∈ T has exactly b immediate successors. A vector homogeneous tree T is a finite sequence (T 1,...,T d ) of homogeneous trees and its level product ?T is the subset of the Cartesian product T 1×...×T d consisting of all finite sequences (t 1,...,t d ) of nodes having common length. We study the behavior of measurable events in probability spaces indexed by the level product ?T of a vector homogeneous tree T. We show that, by refining the index set to the level product ?S of a vector strong subtree S of T, such families of events become highly correlated. An analogue of Lebesgue’s density Theorem is also established which can be considered as the “probabilistic” version of the density Halpern-Läuchli Theorem. 相似文献
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Sotirios Zarogiannis Vassilios Liakopoulos Chrissi Hatzoglou Konstantinos Vogiatzidis Marios Salmas Ioannis Stefanidis Konstantinos Gourgoulianis Paschalis Adam Molyvdas Spiros Lafis 《Analytical sciences》2007,23(5):593-595
This article reports on the development of a simple and cost-effective bioassay for the detection of biotin in urine and serum, based on the very selective binding of avidin and biotin. Avidin was allowed to react without isolating it from egg white. Egg white was treated with the dye HABA, which binds to avidin. Upon subsequent treatment with biotin, HABA is released due to the high affinity of biotin to avidin. The amount of HABA released is proportional to the amount of biotin used. 相似文献
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Konstantinos E. Korontinis Manfred R. Trummer 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1995,46(3):419-444
A fully discrete method is presented for computing inertial manifolds of dissipative partial differential equations. In particular, only an approximate spectral decomposition of the dominant differential operator needs to be known. The first few of the smallest eigenvalues and eigenvectors of the discretized operator are approximated using the Lanczos algorithm. Numerical experiments are performed for an equation in one space dimension by discretizing the space variable on a sufficiently fine grid. The basic ideas and techniques are exemplified for selected bifurcation diagrams of an integrated form of the Kuramoto-Sivashinsky equation.This research was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) grant OGP0036901, NSERC and Schweizerischer Nationalfonds zur Förderung der Wissenschaften BEF 0150297, and Forschungsinstitut für Mathematik, ETH Zürich. 相似文献
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New Calix[4]arene‐Cored Peripherally Functionalized Dendrimers: Synthesis and Conformational Characteristics
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Georgios Paraskevopoulos Dimitrios Alivertis Vassiliki Theodorou Konstantinos Skobridis 《Helvetica chimica acta》2015,98(5):593-603
New calixarene‐based dendrimers, containing calix[4]arene as the core and different generations of Fréchet‐type poly(benzyl ether) dendrons as building blocks, which possess either Br‐atoms or COOtBu groups at their surface were synthesized and presented herein for the first time. The new calix[4]arene‐cored dendritic macromolecules were fully characterized and found to prefer strictly the cone conformation. 相似文献
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