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81.
The existence of exponential attractor for the diffusive Hindmarsh-Rose equations on a three-dimensional bounded domain in the study of neurodynamics is proved through uniform estimates and a new theorem on the squeezing property of the abstract reaction-diffusion equation established in this paper. This result on the exponential attractor infers that the global attractor whose existence has been proved in [22] for the diffusive Hindmarsh-Rose semiflow has a finite fractal dimension. 相似文献
82.
The permeability of poly(butylene terephthalate) was examined for He, Ne, Ar and CO2 at the temperature range of 293–338 K and an upstream pressure to 1,2 bar. The energies of activation of permeation and diffusion in case of Ne, Ar and CO2 are higher above glass transition temperature than below, while they are nearly constant in case of He. The dependence of temperature of solubility coefficients does not change at the glass transition temperature. 相似文献
83.
Phan Van Cuong Joonghoe Dho Hyo Yeol Park Do-Hyung Kim 《Applied Physics A: Materials Science & Processing》2009,95(2):567-571
This paper reports on the sonochemical-assisted synthesis of La0.7Sr0.3MnO3 (LSMO) nanoparticles (NPs) which have a single-crystalline perovskite structure. The average particle size of LSMO NPs was
controlled from about 40 to 120 nm by changing the annealing temperatures from 750 to 1050°C. The particle size, electrical
resistivity, and ferromagnetic transition temperature of LSMO NPs were strongly dependent on the annealing temperature. A
substantial decrease in resistivity and an enhancement in the insulator–metal transition temperature were found on increasing
the annealing temperature. Furthermore, the enhancement in magnetization and paramagnetic–ferromagnetic (PM–FM) transition
temperatures was observed as the annealing temperature increases. 相似文献
84.
David J. Heldebrant Dr. Clement R. Yonker Dr. Philip G. Jessop Dr. Lam Phan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(31):7619-7627
CO2‐binding organic liquids (CO2BOLs) are mixtures of a base (typically an amidine or guanidine) and an alcohol, and have been shown to reversibly capture and release CO2 with low reaction energies and high gravimetric CO2 capacity. We now report the ability of such liquid blends to chemically bind and release other acid gases such as CS2, COS, and SO2 analogously to CO2. These systems bind with sulfur‐containing acid gases to form colored ionic liquids with new O‐alkylxanthate, O‐alkylthiocarbonyl, and O‐alkylsulfite anions. The capture and thermal stripping of each acid gas from these systems and their applicability towards flue gas desulfurization is discussed. 相似文献
85.
In this paper, we use a simple discrete dynamical model to study integer partitions and their lattice. The set of reachable configurations of the model, with the order induced by the transition rule defined on it, is the lattice of all partitions of a positive integer, equipped with a dominance ordering. We first explain how this lattice can be constructed by an algorithm in linear time with respect to its size by showing that it has a self-similar structure. Then, we define a natural extension of the model to infinity, which we compare with the Young lattice. Using a self-similar tree, we obtain an encoding of the obtained lattice which makes it possible to enumerate easily and efficiently all the partitions of a given integer. This approach also gives a recursive formula for the number of partitions of an integer, and some informations on special sets of partitions, such as length bounded partitions. 相似文献
86.
Hai Yen Thi Phan Takashi Yano Hai Anh Thi Phan Tsuyoshi Nishimura Tetsumi Sato Yoritaka Hashimoto 《Applied Acoustics》2010,71(2):107-114
Vietnam is a developing country in southeast Asia, and its environment has been seriously affected by industrialization and urbanization. In large cities like Hanoi (northern Vietnam) and Ho Chi Minh City (southern Vietnam), noise emission from road traffic has been found to be a serious concern among general public. In 2005 and 2007, two large-scale socio-acoustic surveys of community response to road traffic noise were conducted to investigate human reactions to road traffic noise in these cities; the sample sizes were 1503 people in Hanoi and 1471 in Ho Chi Minh City. The noise exposure levels (Lden) were 70–83 dB in Hanoi and 75–83 dB in Ho Chi Minh City. Noise annoyance was estimated using standardized annoyance scales. For both cities, dose–response relationships were established between Lden and the percentage of highly annoyed respondents. Compared to annoyance responses of European people, Vietnamese were less annoyed by road traffic noise by about 5 dB. Hanoi respondents seemed to be more annoyed by noise than Ho Chi Minh City respondents. Conversation and sleep disturbances were not as serious as expected in either city. Furthermore, window orientation in the home was found to affect activity disturbances. 相似文献
87.
Hoa V. Phan Pradip Chakraborty Meimei Chen Yitzi M. Calm Dr. Kirill Kovnir Lawrence K. Keniley Jr. Jordan M. Hoyt Elisabeth S. Knowles Dr. Céline Besnard Prof. Mark W. Meisel Prof. Andreas Hauser Prof. Catalina Achim Prof. Michael Shatruk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15805-15815
Three iron(II) complexes, [Fe(TPMA)(BIM)](ClO4)2?0.5H2O ( 1 ), [Fe(TPMA)(XBIM)](ClO4)2 ( 2 ), and [Fe(TPMA)(XBBIM)](ClO4)2 ?0.75CH3OH ( 3 ), were prepared by reactions of FeII perchlorate and the corresponding ligands (TPMA=tris(2‐pyridylmethyl)amine, BIM=2,2′‐biimidazole, XBIM=1,1′‐(α,α′‐o‐xylyl)‐2,2′‐biimidazole, XBBIM=1,1′‐(α,α′‐o‐xylyl)‐2,2′‐bibenzimidazole). The compounds were investigated by a combination of X‐ray crystallography, magnetic and photomagnetic measurements, and Mössbauer and optical absorption spectroscopy. Complex 1 exhibits a gradual spin crossover (SCO) with T1/2=190 K, whereas 2 exhibits an abrupt SCO with approximately 7 K thermal hysteresis (T1/2=196 K on cooling and 203 K on heating). Complex 3 is in the high‐spin state in the 2–300 K range. The difference in the magnetic behavior was traced to differences between the inter‐ and intramolecular interactions in 1 and 2 . The crystal packing of 2 features a hierarchy of intermolecular interactions that result in increased cooperativity and abruptness of the spin transition. In 3 , steric repulsion between H atoms of one of the pyridyl substituents of TPMA and one of the benzene rings of XBBIM results in a strong distortion of the FeII coordination environment, which stabilizes the high‐spin state of the complex. Both 1 and 2 exhibit a photoinduced low‐spin to high‐spin transition (LIESST effect) at 5 K. The difference in the character of intermolecular interactions of 1 and 2 also manifests in the kinetics of the decay of the photoinduced high‐spin state. For 1 , the decay rate constant follows the single‐exponential law, whereas for 2 it is a stretched exponential, reflecting the hierarchical nature of intermolecular contacts. The structural parameters of the photoinduced high‐spin state at 50 K are similar to those determined for the high‐spin state at 295 K. This study shows that N‐alkylation of BIM has a negligible effect on the ligand field strength. Therefore, the combination of TPMA and BIM offers a promising ligand platform for the design of functionalized SCO complexes. 相似文献
88.
The paper describes a parallel algorithm for computing an n-dimensional Delaunay tessellation using a divide-conquer strategy. Its implementation (using MPI library for C) in the case
n = 2, relied on restricted areas to discard non-Delaunay edges, is executed easily on PC clusters. We shows that the convexity
is a crucial factor of efficiency of the parallel implementation over the corresponding sequential one. 相似文献
89.
An application of a new standardization method for rapid activation mass analysis with registration of the strongly absorbed low-energy gamma radiation is described. This method makes it possible to avoid the use of the time-consuming and laborious method of Internal Standard. 相似文献
90.