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81.
Delduc Francois Lacroix Sylvain Magro Marc Vicedo Benoît 《Letters in Mathematical Physics》2020,110(7):1645-1687
Letters in Mathematical Physics - In the approach recently proposed by K. Costello and M. Yamazaki, which is based on a four-dimensional variant of Chern–Simons theory, we derive a simple and... 相似文献
82.
Rachna AggarwalAnthony A. Birkbeck Charles B. de KoningRobin G.F. Giles Ivan R. GreenShuk-Hui Li Francois J. Oosthuizen 《Tetrahedron letters》2003,44(24):4535-4538
peri-Interactions are important in determining both the conformation of the dihydropyran ring of 2-benzopyrans as well as the stereochemistry of its substituents. 相似文献
83.
We consider a multi-queue multi-server system with n servers (processors) and m queues. At the system there arrives a stationary and ergodic stream of m different types of requests with service requirements which are served according to the following k-limited head of the line processor sharing discipline: The first k requests at the head of the m queues are served in processor sharing by the n processors, where each request may receive at most the capacity of one processor. By means of sample path analysis and Loynes’
monotonicity method, a stationary and ergodic state process is constructed, and a necessary as well as a sufficient condition
for the stability of the m separate queues are given, which are tight within the class of all stationary ergodic inputs. These conditions lead to tight
necessary and sufficient conditions for the whole system, also in case of permanent customers, generalizing an earlier result
by the authors for the case of n=k=1.
This work was supported by a grant from the Siemens AG. 相似文献
84.
Francois Ribot Delphine Veautier Steve Guillaudeu Thierry Lalot 《Journal of Sol-Gel Science and Technology》2004,32(1-3):37-41
Hybrid copolymers have been prepared by free radical polymerization, in toluene, of methylacrylate (MA) and varying amounts of an organotin oxo-cluster functionalized with two acrylamido groups, {(BuSn)12O14(OH)6}(AMPS)2. The tin based nanobuilding block is fully preserved in the final materials. These copolymers formed networks where the cross-linking is based on the electrostatic interactions that take place between the macrocation {(BuSn)12O14(OH)6}2 + and its two functional anions (AMPS–). Accordingly, these copolymers can yield gels or solutions depending on the solvent used to swell them. 相似文献
85.
Francois Descouens 《Journal of Combinatorial Theory, Series A》2008,115(3):361-375
Hall-Littlewood functions indexed by rectangular partitions, specialized at primitive roots of unity, can be expressed as plethysms. We propose a combinatorial proof of this formula using Schilling's bijection between ribbon tableaux and ribbon rigged configurations. 相似文献
86.
A sandwich technique based on the very affinity between avidin and biotin is used. Antibodies are covalently bound to glass-fibre on which the antigen is captured. The discs are then treated in sequence with monoclonal antibodies of high selectivity, species-specific anti-IgG (biotin-linked), streptavidin and β-galactosidase, (biotin-linked). The discs are then incubated with the substrate, 4-methylumbelliferyl-β-d-galactopyranoside and the fluorescence is measured in an automatic immunoassay system. 相似文献
87.
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88.
Vacuum Flash Pyrolysis (VFP) at ca. 450–500°C and ca. 0.1–0.3 Torr of the spirocyclic malonyl peroxides () affords high yields of allenes (), while the simple malonyl peroxide () leads to ketone (), derived respectively from decarboxylation and decarbonylation of the intermediary α-lactones (). 相似文献
89.
Claude Mathis Lydia Christmann-Lamande Bernard Francois 《Journal of polymer science. Part A, Polymer chemistry》1980,18(2):671-679
The self-deactivation of polystyryl-barium and polystyryl-strontium in tetrahydrofuran (THF) results essentially from protonation by the solvent. The deactivation constant kd of this reaction is independent of carbanion concentration, length, and functionality of chains. Relations of kd with temperature are: polystyryl-barium: kd = 6.25 × 107 exp(-18,900/RT) sec?1; polystyryl-strontium: kd = 4.1 × 106 exp(?16,000/RT) sec?1. The self-deactivation of α,ω-dicarbanionic oligostyryl-barium is a nonrandomlike reaction. Residual living oligomers are left dicarbanionic even if an important deactivation occurs. 相似文献
90.
Synthesis of diastereoisomeric manganese complexes is described, starting from LMn(CO)3, carbonyl substitutions gave LMn(CO)(PPh3)[P(OMe)3] (L = h5-C5H3, 1-CO2Me, 3-Me). 相似文献