Large Deviation Principle for Additive Functionals of Brownian Motion Corresponding to Kato Measures

Let (B _t ,P ^W _x ) be the Brownian motion. Let be a Radon measure in the Kato class and A _t the additive functional associated with . We prove that A _t /t obeys the large deviation principle.     

Compartmentalization in TEMPO‐Mediated Radical Polymerization in Dispersed Systems: Effects of Macroinitiator Concentration

The influence of the initial macroinitiator concentration ([PT]₀) on compartmentalization effects (segregation effects and confined space effects) in 2,2,6,6‐tetramethylpiperidinyl‐1‐oxy (TEMPO)‐mediated radical polymerization of styrene in a dispersed system at 125 °C has been investigated by simulations employing modified Smith‐Ewart equations. The modeling approach accounts for compartmentalization of both propagating radicals and nitroxide, as well as the generation of radicals by thermal initiation of styrene. The manifestation of compartmentalization effects occurs at significantly greater particle diameters (d) for low [PT]₀; at [PT]₀ = 0.002 M , the polymerization rate, control and livingness are affected by compartmentalization for d < 120 nm, whereas the system behaves as in the corresponding bulk system for d > 45 nm at [PT]₀ = 0.2 M . The results are discussed with regards to the specific effects of compartmentalization on deactivation and bimolecular termination.

     

Efficient synthesis of poly(phenylazomethine) dendrons allowing access to higher generation dendrimers

We have developed a novel synthetic method of phenylazomethine dendrons that uses 4,4'-methylenedianiline instead of 4,4'-diaminobenzophenone to synthesize the precursor of the phenylazomethine dendron and then oxidized the precursor to the next-generation dendron. For this method, the productivity of the dendrons has been significantly increased. Furthermore, as the synthesis of high-generation dendrons becomes easier, synthesis of DPA G5 was achieved. [structure--see text]     

On the global wellposedness for the nonlinear Schrödinger equations with L p -large initial data

We consider the Cauchy problem for the nonlinear Schrödinger equations $ \begin{array}{l} iu_t + \triangle u \pm |u|^{p-1}u =0, \qquad x \in \mathbb{R}^d, \quad t \in \mathbb{R} \\ u(x,0)= u_0(x), \qquad x \in \mathbb{R}^d \end{array} $ for 1 < p < 1 + 4/d and prove that there is a ${\rho (p ,d) \in (1,2)}We consider the Cauchy problem for the nonlinear Schr?dinger equations

l iut + \triangle u ±|u|p-1u = 0,        x ? \mathbbRd,     t ? \mathbbR u(x,0) = u0(x),        x ? \mathbbRd \begin{array}{l} iu_t + \triangle u \pm |u|^{p-1}u =0, \qquad x \in \mathbb{R}^d, \quad t \in \mathbb{R} \\ u(x,0)= u_0(x), \qquad x \in \mathbb{R}^d \end{array}      106. Synthesis of (Z)‐1‐Aza‐1,3‐enynes by the Cross‐Coupling of Terminal Alkynes with Isocyanides Catalyzed by Rare‐Earth Metal Complexes      Wen‐Xiong Zhang  Masayoshi Nishiura  Zhaomin Hou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2008,120(50):9846-9849       107. Gaugeability for Feynman-Kac functionals with applications to symmetric -stable processes      Masayoshi Takeda 《Proceedings of the American Mathematical Society》2006,134(9):2729-2738 For symmetric -stable processes, an analytic criterion for a measure being gaugeable was obtained by Z.-Q. Chen (2002), M. Takeda (2002) and M. Takeda and T. Uemura (2004). Applying it, we consider the ultracontractivity of Feynman-Kac semigroups and expectations of the number of branches hitting closed sets in branching symmetric -stable processes.       108. Anionic polymerization of methacrylates by samarium (III) enolate on networked polystyrene: Effects of its sterically confined environment on polymerization behavior      Daisuke Nagai  Asuka Fujii  Masayoshi Tanaka  Bungo Ochiai  Atsushi Sudo  Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2009,47(6):1510-1521 Anionic polymerization of methacrylates under sterically confined environment in a spherical beads‐shaped networked polystyrene (NwPS) matrix is described. The initiator used herein is a samarium (Sm) (III) enolate, which was formed by treatment of 2‐bromoisobutylate immobilized in the side chain of NwPS with Sm (II) iodide. By using this NwPS‐bound initiator, polymerization of a series of methacrylates (=solid‐supported polymerization) was studied to find its two aspects: (1) In the early stages, the rate constant for each methacrylate was comparable to that for its conventional solution‐phase polymerization using a Sm (III) enolate, suggesting that methacrylate can be efficiently supplied to the propagating end by its free permeation without any interference by the networked structure of the matrix. (2) After the early stages, the rate constant decreased remarkably, implying that permeation of methacrylate was sterically interfered by the formed poly(methacrylate) that filled the confined space in NwPS, as supported by a SEM image of the resulting beads, of which pores were filled with the formed polymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1510–1521, 2009      109. Samarium enolate on crosslinked polystyrene beads. III. Anionic initiator for well‐defined synthesis of poly(hydroxyethyl methacrylate) on solid support      Masayoshi Tanaka  Atsushi Sudo  Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(17):4417-4423 A solid‐supported samarium enolate successfully initiated the polymerization of 2‐(trimethylsilyloxy)ethyl methacrylate (TMS‐HEMA) through the living anionic process. In addition, the silyl group was readily removed by treatment of the beads with a weak acid to afford the corresponding well‐defined poly(methacrylate) having a hydroxyethyl group in the side chain (PHEMA). The hydroxyl group of the immobilized PHEMA on the beads was successfully acetylated to give poly(2‐acetoxyethyl methacrylate), which could be quantitatively isolated from the beads by trifluoroacetic acid treatment. Moreover, the hydroxyl group of the immobilized PHEMA could be utilized as an initiator for acid promoted ring opening polymerization of lactone to yield the corresponding graft copolymer. In this method, the residual and excess reagents could be removed by filtration, which demonstrated the applicability of the present technique to a novel method for construction of functional polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4417–4423, 2004      110. Carboxylation of alkylboranes by N-heterocyclic carbene copper catalysts: synthesis of carboxylic acids from terminal alkenes and carbon dioxide      Ohishi T  Zhang L  Nishiura M  Hou Z 《Angewandte Chemie (International ed. in English)》2011,50(35):8114-8117 Caught in the act: N-Heterocyclic carbene copper(I) complexes (1; IPr=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) serve as an excellent catalyst for the carboxylation of alkylboranes (2; R=alkyl) with CO(2) to afford a variety of functionalized carboxylic acids (3) in high yields. A novel copper methoxide/alkylborane adduct (A) and its subsequent CO(2) insertion product (B) have been isolated and shown to be true active catalyst species.      [首页] « 上一页 [6] [7] [8] [9] [10] 11 [12] [13] [14] [15] [16] 下一页 » 末  页»

Gaugeability for Feynman-Kac functionals with applications to symmetric -stable processes

For symmetric -stable processes, an analytic criterion for a measure being gaugeable was obtained by Z.-Q. Chen (2002), M. Takeda (2002) and M. Takeda and T. Uemura (2004). Applying it, we consider the ultracontractivity of Feynman-Kac semigroups and expectations of the number of branches hitting closed sets in branching symmetric -stable processes.

     

Anionic polymerization of methacrylates by samarium (III) enolate on networked polystyrene: Effects of its sterically confined environment on polymerization behavior

Anionic polymerization of methacrylates under sterically confined environment in a spherical beads‐shaped networked polystyrene (NwPS) matrix is described. The initiator used herein is a samarium (Sm) (III) enolate, which was formed by treatment of 2‐bromoisobutylate immobilized in the side chain of NwPS with Sm (II) iodide. By using this NwPS‐bound initiator, polymerization of a series of methacrylates (=solid‐supported polymerization) was studied to find its two aspects: (1) In the early stages, the rate constant for each methacrylate was comparable to that for its conventional solution‐phase polymerization using a Sm (III) enolate, suggesting that methacrylate can be efficiently supplied to the propagating end by its free permeation without any interference by the networked structure of the matrix. (2) After the early stages, the rate constant decreased remarkably, implying that permeation of methacrylate was sterically interfered by the formed poly(methacrylate) that filled the confined space in NwPS, as supported by a SEM image of the resulting beads, of which pores were filled with the formed polymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1510–1521, 2009     

Samarium enolate on crosslinked polystyrene beads. III. Anionic initiator for well‐defined synthesis of poly(hydroxyethyl methacrylate) on solid support

A solid‐supported samarium enolate successfully initiated the polymerization of 2‐(trimethylsilyloxy)ethyl methacrylate (TMS‐HEMA) through the living anionic process. In addition, the silyl group was readily removed by treatment of the beads with a weak acid to afford the corresponding well‐defined poly(methacrylate) having a hydroxyethyl group in the side chain (PHEMA). The hydroxyl group of the immobilized PHEMA on the beads was successfully acetylated to give poly(2‐acetoxyethyl methacrylate), which could be quantitatively isolated from the beads by trifluoroacetic acid treatment. Moreover, the hydroxyl group of the immobilized PHEMA could be utilized as an initiator for acid promoted ring opening polymerization of lactone to yield the corresponding graft copolymer. In this method, the residual and excess reagents could be removed by filtration, which demonstrated the applicability of the present technique to a novel method for construction of functional polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4417–4423, 2004     

Carboxylation of alkylboranes by N-heterocyclic carbene copper catalysts: synthesis of carboxylic acids from terminal alkenes and carbon dioxide

Caught in the act: N-Heterocyclic carbene copper(I) complexes (1; IPr=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) serve as an excellent catalyst for the carboxylation of alkylboranes (2; R=alkyl) with CO(2) to afford a variety of functionalized carboxylic acids (3) in high yields. A novel copper methoxide/alkylborane adduct (A) and its subsequent CO(2) insertion product (B) have been isolated and shown to be true active catalyst species.