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811.
Rather B Moulton B Walsh RD Zaworotko MJ 《Chemical communications (Cambridge, England)》2002,(7):694-695
Self-assembly of Zn(NO3)2 with m-pyridinecarboxylate (nicotinate) under mild conditions affords several products including a novel three-dimensional network [Zn(nicotinate)2]n that has connectivity defined by the circuit symbol 4(2).8(4). 相似文献
812.
[reaction: see text] Starting from readily available precursors, selenoglycosides derived from GalNAc, GlcNAc, and ManNAc were prepared by either a one- or a two-step process. The anomeric selenides underwent facile C-Se homolysis to provide the corresponding anomeric radicals, which were trapped with alkenes to give C-glycosides. This provides a general entry to alpha-C-glycosides based on 2-amino-2-deoxy sugars that is also applicable to disaccharide variants. 相似文献
813.
C. Domshlak S. Prestwich F. Rossi K. B. Venable T. Walsh 《Journal of Heuristics》2006,12(4-5):263-285
Many real life optimization problems are defined in terms of both hard and soft constraints, and qualitative conditional preferences.
However, there is as yet no single framework for combined reasoning about these three kinds of information. In this paper
we study how to exploit classical and soft constraint solvers for handling qualitative preference statements such as those
captured by the CP-nets model. In particular, we show how hard constraints are sufficient to model the optimal outcomes of
a possibly cyclic CP-net, and how soft constraints can faithfully approximate the semantics of acyclic conditional preference
statements whilst improving the computational efficiency of reasoning about these statements.
This material is based in part upon works supported by the Science Foundation Ireland under Grant No. 00/PI.1/C075 相似文献
814.
815.
816.
Electrically active fibrous filters, that is fibrous filters whose fibres carry a permanent electric charge, are an increasingly popular alternative to conventional fibrous filters in applications where low pressure drop and high collection efficiencies are critical. The advantage of these materials is the additional collection efficiency, due to electrostatic mechanisms, that can be achieved without pressure drop increase. The efficiency of these materials can fall as they are loaded with aerosol particles, so it is necessary that proper account be taken of this process during use. A complete understanding of the mechanisms responsible for this reduction in efficiency has not yet been reached. An experimental study has been undertaken at Loughborough University of Technology investigating the loading behaviour of a mixed fibre type electrically active material. The experimental techniques used in this work and experimental findings with a range of aerosol particle sizes are reported here. 相似文献
817.
We study the class of directed graphs that have indegree = outdegree = 2 at every vertex. These digraphs can be decomposed uniquely into “alternating cycles”, we use this decomposition to present efficient techniques for counting and generating them. The number (up to isomorphism) of these digraphs and the number of connected ones on up to 20 vertices have been computed and are presented. 相似文献
818.
All-or-nothing demands and start-up costs for nonmarket goods are discussed within the framework of price discrimination models. We show that in an all-or-nothing bid situation, consumers will provide average rather than marginal values resulting in overstatement of consumers' surplus. Nonmarket goods are often provided under conditions which are exacerbated by start-up costs. Empirical measurement of nonmarket demand can contain significant error if these concepts are not properly applied. 相似文献
819.
We present the helicity formalism fore + e? annihilation into two-body resonance states, and show how to systematically extract the magnitudes and relative phases of the form factors present in the one-photon exchange approximation. This entails measurement of one-particle density matrices and certain polarization correlations in the final state. We discuss, as an example, the vector meson dominance expectations for annihilation into meson resonances and show how this model can be tested. 相似文献
820.
The field of Small Molecule Microarray's (SMM's) is an ever-expanding part of the larger microarray field. SMM's are array based detection systems that use small molecules as probes immobilized on a variety of microarray surfaces that are screened against a number of targets for purposes including, but not limited to, protein-small molecule ligand recognition and protein function profiling. This review covers the recent advances in the field with particular emphasis on the successful applications of SMM's, as well as technical advances in platform optimization and novel small molecule immobilization strategies. 相似文献