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B. K. Ane A. M. Tarasyev C. Watanabe 《Journal of Optimization Theory and Applications》2007,134(2):321-338
The paper introduces a dynamic model of optimization of R&D intensity under the effect of technology assimilation. The model
involves R&D investments, technology stock, production, and technology productivity as main variables. The model characterizes
the “growth” and “decline” trends that describe the interaction between R&D investments and transformation process of production
factors. The technology stock is constructed as a function of indigenous and exogenous technology stocks and their growth
rates. The research focuses on the issue of a reasonable balance between the indigenous technology stock and assimilated technology
flow. Econometric linearization of the technology assimilation effect is used to construct a reasonable optimal control model.
The existence of the value function for the problem of the optimal economic growth on the infinite horizon is proved and the
basic features of the value function are outlined. The property of strong invariance for the main proportions of the model
such as technology productivity and R&D intensity is proved. The model is calibrated on the aggregate data of the Japanese
automotive industry.
The research was sponsored by the SIMOT Program of the Japanese Ministry of Education, Science and Technology.
The second author was supported by the Russian Fund for Basic Research, Grants 05-01-00601, 05-01-08034, by the Russian Fund
for Humanities, Grant RFH 05-02-02118a, and by the Program for the Sponsorship of Leading Scientific Schools, Grant NSCH-791.2003.1. 相似文献
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The structures and relative stabilities of the complexes formed by uracil and its thio- and seleno-derivatives with the Sr(2+) cation, in the gas phase, have been analyzed by means of G96LYP density functional theory (DFT) calculations. The attachment of the Sr(2+) cation to the heteroatom at position 4 is preferred systematically. Although the enolic forms of uracil and its derivatives should not be observed in the gas phase, the corresponding Sr(2+) complexes are the most stable. The enhanced stability of these tautomers is two-fold, on the one hand Sr(2+) interacts with two basic sites simultaneously, and on the other hand an aromatization of the six-membered ring takes place upon Sr(2+) association. Sr(2+) attachment also has a clear catalytic effect in the tautomerization processes involving uracil and its derivatives. This catalytic effect increases when oxygen is replaced by sulfur or selenium. The Sr(2+) binding energy with uracil and its derivatives is bigger than the tautomerization barriers connecting the dioxo forms with the corresponding enolic tautomers. Consequently, when associated with Sr(2+), all tautomers are energetically accessible and should all be observed in the gas phase. 相似文献
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Arrizabalaga-Larrañaga Ane Rodríguez Pilar Medina Mireia Santos F. Javier Moyano Encarnación 《Analytical and bioanalytical chemistry》2019,411(21):5577-5591
Analytical and Bioanalytical Chemistry - This work describes the development of an ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method for the... 相似文献
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Short Access to Belt Compounds with Spatially Close CC Bonds and Their Transannular Reactions 下载免费PDF全文
Prof. Dr. Pelayo Camps Dr. Tània Gómez Ane Otermin Dr. Mercè Font‐Bardia Dr. Carolina Estarellas Prof. Dr. Francisco Javier Luque 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(40):14036-14046
Two domino Diels–Alder adducts were obtained from 3,7‐bis(cyclopenta‐2,4‐dien‐1‐ylidene)‐cis‐bicyclo[3.3.0]octane and dimethyl acetylenedicarboxylate or N‐methylmaleimide under microwave irradiation. From the first adduct, a C20H24 diene with C2v symmetry was obtained by Zn/AcOH reduction, hydrolysis, oxidative decarboxylation, and selective hydrogenation. Photochemical [2+2] cycloaddition of this diene gave a thermally unstable cyclobutane derivative, which reverts to the diene. However, both the diene and the cyclobutane derivatives could be identified by X‐ray diffraction analysis upon irradiation of the diene crystal. New six‐membered rings are formed upon the transannular addition of bromine or iodine to the diene. The N‐type selectivity of the addition was examined by theoretical calculations, which revealed the distinct susceptibility of the doubly bonded carbon atoms to the bromine attack. 相似文献
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David Albesa‐Jov Fernanda Mendoza Ane Rodrigo‐Unzueta Fernando Gomolln‐Bel Javier O. Cifuente Saioa Urresti Natalia Comino Hansel Gmez Javier Romero‐García Jos M. Lluch Enea Sancho‐Vaello Xevi Biarns Antoni Planas Pedro Merino Laura Masgrau Marcelo E. Guerin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(34):10036-10040
Glycosyltransferases (GTs) comprise a prominent family of enzymes that play critical roles in a variety of cellular processes, including cell signaling, cell development, and host–pathogen interactions. Glycosyl transfer can proceed with either inversion or retention of the anomeric configuration with respect to the reaction substrates and products. The elucidation of the catalytic mechanism of retaining GTs remains a major challenge. A native ternary complex of a GT in a productive mode for catalysis is reported, that of the retaining glucosyl‐3‐phosphoglycerate synthase GpgS from M. tuberculosis in the presence of the sugar donor UDP‐Glc, the acceptor substrate phosphoglycerate, and the divalent cation cofactor. Through a combination of structural, chemical, enzymatic, molecular dynamics, and quantum‐mechanics/molecular‐mechanics (QM/MM) calculations, the catalytic mechanism was unraveled, thereby providing a strong experimental support for a front–side substrate‐assisted SNi‐type reaction. 相似文献
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Ane M. Zaldua M. Eugenia Muoz Juan J. Pea Anton Santamaría 《Macromolecular rapid communications》1995,16(6):417-424
Rheological and thermal analysis results of blends of a thermotropic copolyesteramide and polyarylate of bisphenol A depend on the thermo-mechanical treatment during mixing. The changes observed as mixing time increases are the following: (a) melt viscosity and loss factor increase, (b) glass transition temperature decreases. The morphological analysis of the blends shows the inability of the treated blends to form an oriented liquid crystalline polymer (LCP) phase, which explains the observed viscoelastic properties. 相似文献
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Irene V. J. Feiner Krishna R. Pulagam Vanessa Gómez-Vallejo Kepa Zamacola Zuriñe Baz María M. Caffarel Charles H. Lawrie Ane Ruiz-de-Angulo Mónica Carril Jordi Llop 《Particle & Particle Systems Characterization》2020,37(12):2000200
Boron neutron capture therapy (BNCT) is a binary approach for cancer treatment in which boron-10 atoms and thermal neutrons need to colocalize to become effective. Recent research in the development of BNCT drug candidates focuses increasingly on nanomaterials, with the advantages of high boron loadings and passive targeting due to the enhanced permeability and retention (EPR) effect. The use of small boron-rich gold nanoparticles (AuNPs) in combination with a pretargeting approach is proposed. Small sized polyethylene glycol–stabilized AuNPs (core size 4.1 ± 1.5 nm), are synthesized and functionalized with thiolated cobalt bis(dicarbollide) and tetrazine. To enable in vivo tracking of the AuNPs by positron emission tomography (PET), the core is doped with [64Cu]CuCl2. For the pretargeting approach, the monoclonal antibody Trastuzumab is functionalized with trans-cyclooctene-N-hydroxysuccinimide ester. After proving in vitro occurrence of the antibody conjugation onto the AuNPs by click reaction and the low toxicity of the AuNPs, the boron delivery system is evaluated in vivo using breast cancer xenograft bearing mice and PET imaging. Tumor uptake due to the EPR effect can be witnessed with ≈5% injected dose (ID) cm−3 at 24 h postinjection, but with slower clearance than expected. Therefore, no increased retention can be observed using the pretargeting strategy. 相似文献