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The resemblance between colloidal and molecular polymerization reactions is very useful in fundamental studies of polymerization reactions, as well as in the development of new nanoscale systems with desired properties. Future applications of colloidal polymers will require nanoparticle ensembles with a high degree of complexity that can be realized by hetero‐assembly of NPs with different dimensions, shapes, and compositions. A method has been developed to apply strategies from molecular copolymerization to the co‐assembly of gold nanorods with different dimensions into random and block copolymer structures (plasmonic copolymers). The approach was extended to the co‐assembly of random copolymers of gold and palladium nanorods. A kinetic model validated and further expanded the kinetic theories developed for molecular copolymerization reactions.  相似文献   
43.
Starting from a readily available enantiopure building block, a straightforward enantioselective approach to 3′-methyl-2′,3′-β-oxirane-fused carbanucleosides bearing adenosine analogues is detailed. The key steps in the syntheses involved a lipase-catalyzed regioselective monoacylation of a diol to obtain the key intermediate and direct coupling of this key intermediate with diversely substituted purine nucleobases under Mitsunobu reaction conditions providing only the N9 target molecules.  相似文献   
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By topological arguments, we set forth sufficient hypotheses for a given function K, on a compact Riemannian manifold (M, g), to be the scalar curvature of a metric conformal to g.  相似文献   
46.
We state and prove a “Lax–Hopf formula” characterizing viable capture basins of targets investigated in viability theory and derive a “Max-Plus” morphism of capture basins with respect to the target. Capture basins are used to define “viability solutions” to Hamilton–Jacobi equations satisfying “trajectory conditions” (initial, boundary or Lagrangian conditions). The Max-Plus morphism property of Lax–Hopf formula implies the fact that the solution associated with inf-convolution of trajectory conditions is the inf-convolution of the solutions for each trajectory condition. For instance, Lipschitz regularization or decreasing envelopes of trajectory condition imply the Lipschitz regulation or decreasing envelopes of the solutions.  相似文献   
47.
The synthesis of fluorinated synthetic intermediates has become a field of intense research in organic chemistry. In this article, we report the application of a gold-catalyzed rearrangement to the synthesis of β-trifluoromethylated α,β-unsaturated ketones. The scope of the reaction, as well as the valorization of the products in subsequent transformations has been investigated. This study allowed for the preparation of various CF3-substituted enones and fluorinated Diels-Alder adducts from easily accessible starting materials.  相似文献   
48.
Several single phase hollandite ceramics having Ba2+ x Cs+ y (C = Al,Fe)3+ 2x+y Ti4+ 8?2x?y O16 composition have been synthesized and irradiated under external electron beams simulating the β-irradiation of radioactive cesium. These samples have been characterized by 57Fe transmission Mössbauer spectroscopy. Mössbauer results show that the irradiation modifies the local arrangements of Ba cations around Fe3+ ions by atomic displacement of Ba ions.  相似文献   
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We compute the Clarke generalized gradient of the marginal function of a nonconvex optimization problem with respect to usual and non usual parameters and we show how Lagrange multipliers are involved in this formula.  相似文献   
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