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111.
Cedric Lecouvey 《Journal of Algebraic Combinatorics》2003,18(2):99-133
We use Kashiwara's theory of crystal bases to study plactic monoids for U
q(so
2n+1) and U
q(so
2n
). Simultaneously we describe a Schensted type correspondence in the crystal graphs of tensor powers of vector and spin representations and we derive a Jeu de Taquin for type B from the Sheats sliding algorithm. 相似文献
112.
The statement (and the proof) of Theorem 4.1.1 of the paperMackey formula in type A [Proc. London. Math.Soc. (3) 80 (2000) 545574] is false. In this corrigendumwe provide a correct statement (and a correct proof). As a consequence,we see that Corollary 4.1.2 of the paper holds. So all the otherstatements in the paper are correct (up to minor misprints...).2000 Mathematical Subject Classification: 20G05, 20G40. 相似文献
113.
Hong Jun ZhouKa Fai Cedric Yiu Leong Kwan Li 《Journal of Computational and Applied Mathematics》2011,235(13):3921-3931
In this paper, American put options on zero-coupon bonds are priced under a single factor model of short-term rate. The linear complementarity problem of the option value is solved numerically by a penalty method, by which the problem is transformed into a nonlinear PDE by adding a power penalty term. The solution of the penalized problem converges to that of the original problem. A numerical scheme is established by using the finite volume method and the corresponding stability and convergence are discussed. Numerical results are presented to show the usefulness of the method. 相似文献
114.
Invariant pairs have been proposed as a numerically robust means to represent and compute several eigenvalues along with the corresponding (generalized) eigenvectors for matrix eigenvalue problems that are nonlinear in the eigenvalue parameter. In this work, we consider nonlinear eigenvalue problems that depend on an additional parameter and our interest is to track several eigenvalues as this parameter varies. Based on the concept of invariant pairs, a theoretically sound and reliable numerical continuation procedure is developed. Particular attention is paid to the situation when the procedure approaches a singularity, that is, when eigenvalues included in the invariant pair collide with other eigenvalues. For the real generic case, it is proven that such a singularity only occurs when two eigenvalues collide on the real axis. It is shown how this situation can be handled numerically by an appropriate expansion of the invariant pair. The viability of our continuation procedure is illustrated by a numerical example. 相似文献
115.
Nazeeruddin MK Wang Q Cevey L Aranyos V Liska P Figgemeier E Klein C Hirata N Koops S Haque SA Durrant JR Hagfeldt A Lever AB Grätzel M 《Inorganic chemistry》2006,45(2):787-797
A new ruthenium(II) complex, tetrabutylammonium [ruthenium (4-carboxylic acid-4'-carboxylate-2,2'-bipyridine)(4,4'-di(2-(3,6-dimethoxyphenyl)ethenyl)-2,2'-bipyridine)(NCS)(2)] (N945H), was synthesized and characterized by analytical, spectroscopic, and electrochemical techniques. The absorption spectrum of the N945H sensitizer is dominated by metal-to-ligand charge-transfer (MLCT) transitions in the visible region, with the lowest allowed MLCT bands appearing at 25 380 and 18 180 cm(-1). The molar extinction coefficients of these bands are 34 500 and 18 900 M(-1) cm(-1), respectively, and are significantly higher when compared to than those of the standard sensitizer cis-dithiocyanatobis(4,4'-dicarboxylic acid-2,2'-bipyridine)ruthenium(II). An INDO/S and density functional theory study of the electronic and optical properties of N945H and of N945 adsorbed on TiO(2) was performed. The calculations point out that the top three frontier-filled orbitals have essentially ruthenium 4d (t(2g) in the octahedral group) character with sizable contribution coming from the NCS ligand orbitals. Most critically the calculations reveal that, in the TiO(2)-bound N945 sensitizer, excitation directs charge into the carboxylbipyridine ligand bound to the TiO(2) surface. The photovoltaic data of the N945 sensitizer using an electrolyte containing 0.60 M butylmethylimidazolium iodide, 0.03 M I(2), 0.10 M guanidinium thiocyanate, and 0.50 M tert-butylpyridine in a mixture of acetonitrile and valeronitrile (volume ratio = 85:15) exhibited a short-circuit photocurrent density of 16.50 +/- 0.2 mA cm(-2), an open-circuit voltage of 790 +/- 30 mV, and a fill factor of 0.72 +/- 0.03, corresponding to an overall conversion efficiency of 9.6% under standard AM (air mass) 1.5 sunlight, and demonstrated a stable performance under light and heat soaking at 80 degrees C. 相似文献
116.
In this paper we develop set of novel Markov chain Monte Carlo algorithms for Bayesian smoothing of partially observed non-linear
diffusion processes. The sampling algorithms developed herein use a deterministic approximation to the posterior distribution
over paths as the proposal distribution for a mixture of an independence and a random walk sampler. The approximating distribution
is sampled by simulating an optimized time-dependent linear diffusion process derived from the recently developed variational
Gaussian process approximation method. The novel diffusion bridge proposal derived from the variational approximation allows
the use of a flexible blocking strategy that further improves mixing, and thus the efficiency, of the sampling algorithms.
The algorithms are tested on two diffusion processes: one with double-well potential drift and another with SINE drift. The
new algorithm’s accuracy and efficiency is compared with state-of-the-art hybrid Monte Carlo based path sampling. It is shown
that in practical, finite sample applications the algorithm is accurate except in the presence of large observation errors
and low observation densities, which lead to a multi-modal structure in the posterior distribution over paths. More importantly,
the variational approximation assisted sampling algorithm outperforms hybrid Monte Carlo in terms of computational efficiency,
except when the diffusion process is densely observed with small errors in which case both algorithms are equally efficient. 相似文献
117.
Today the capability to rationally design and construct hybrid materials utilizing a performance-property driven methodology is strongly dependent on our ability to control the structure and the dynamics of hybrid interfaces. This control needs a deep knowledge of their molecular and supramolecular dynamics that must be evaluated in situ, in the soft matter or colloidal states. For this purpose the use of modern methodologies of characterization such as time resolved synchrotron experiments and advanced pulsed field gradient NMR methods (DOSY) is particularly relevant. In this critical review, two important examples are discussed. They concern, first, the study of surface capping organic components' affinity towards nanoparticle surfaces by DOSY NMR. The knowledge and therefore the tuning of this affinity is paramount because it controls solubility, transferability and stability of colloidal dispersions of nanoparticles (NPs). In the second part, the mechanism of micellar templated formation of hybrid mesophases will be discussed in the frame of the main results obtained via in situ SAXS (107 references). 相似文献
118.
An efficient modified Hantzsch reaction is described for the synthesis of optically pure thiazole amino acid derivatives from the corresponding amino acids. The method is exemplified by the synthesis of a derivative of L-(Gln)Thz, the novel chiral thiazole amino acid moiety of dolastatin 3. The Cotton effects of thiazole amino acids correlate well with the absolute stereochemistry of these compounds. 相似文献
119.
Kristiansen UR Mattei PO Pinhede C Amielh M 《The Journal of the Acoustical Society of America》2011,130(4):1851-1855
It is well known that airflow in a corrugated pipe can excite whistling at the frequencies of the pipe's longitudinal acoustic modes. This short contribution reports on the results of experiments where a low frequency, oscillating flow with velocity magnitudes of the same order as the airflow has been added. Depending on the oscillation strength, it has been found that this flow may silence the pipe or move the whistling to higher harmonics. It is also shown that the low frequency oscillation itself may excite higher frequency whistling sounds in the pipe. 相似文献
120.
Feyisara Eyiwumi Oni Qassim Esmaeel Joseph Tobias Onyeka Rasheed Adeleke Cedric Jacquard Christophe Clement Harald Gross Essaid Ait Barka Monica Hfte 《Molecules (Basel, Switzerland)》2022,27(2)
Pseudomonas lipopeptides (Ps-LPs) play crucial roles in bacterial physiology, host–microbe interactions and plant disease control. Beneficial LP producers have mainly been isolated from the rhizosphere, phyllosphere and from bulk soils. Despite their wide geographic distribution and host range, emerging evidence suggests that LP-producing pseudomonads and their corresponding molecules display tight specificity and follow a phylogenetic distribution. About a decade ago, biocontrol LPs were mainly reported from the P. fluorescens group, but this has drastically advanced due to increased LP diversity research. On the one hand, the presence of a close-knit relationship between Pseudomonas taxonomy and the molecule produced may provide a startup toolbox for the delineation of unknown LPs into existing (or novel) LP groups. Furthermore, a taxonomy–molecule match may facilitate decisions regarding antimicrobial activity profiling and subsequent agricultural relevance of such LPs. In this review, we highlight and discuss the production of beneficial Ps-LPs by strains situated within unique taxonomic groups and the lineage-specificity and coevolution of this relationship. We also chronicle the antimicrobial activity demonstrated by these biomolecules in limited plant systems compared with multiple in vitro assays. Our review further stresses the need to systematically elucidate the roles of diverse Ps-LP groups in direct plant–pathogen interactions and in the enhancement of plant innate immunity. 相似文献