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1.
J. Łukasik G. Auger M. L. Begemann-Blaich N. Bellaize R. Bittiger F. Bocage B. Borderie R. Bougault B. Bouriquet J. L. Charvet A. Chbihi R. Dayras D. Durand J. D. Frankland E. Galichet D. Gourio D. Guinet S. Hudan P. Lautesse F. Lavaud A. Le Fèvre R. Legrain O. Lopez U. Lynen W. F. J. Müller L. Nalpas H. Orth E. Plagnol E. Rosato A. Saija C. Schwarz C. Sfienti B. Tamain W. Trautmann A. Trzciński K. Turzó E. Vient M. Vigilante C. Volant B. Zwiegliński 《Acta Physica Hungarica A》2006,25(2-4):229-239
Directed and elliptic flow for the 197Au+197Au system at incident energies between 40 and 150 MeV per nucleon has been measured using the INDRA 4π multi-detector. For semi-central collisions, the excitation function of elliptic flow shows a transition from in-plane to out-of-plane emission at around 100 MeV per nucleon. The directed flow changes sign at a bombarding energy between 50 and 60 MeV per nucleon and remains negative at lower energies. Molecular dynamics calculations (CHIMERA) indicate sensitivity of the global squeeze-out transition on the σ NN and demonstrate the importance of angular momentum conservation in transport codes at low energies. 相似文献
2.
We redraw, using state-of-the-art methods for free-energy calculations, the phase diagrams of two reference models for the liquid state: the Gaussian and inverse-power-law repulsive potentials. Notwithstanding the different behaviors of the two potentials for vanishing interparticle distances, their thermodynamic properties are similar in a range of densities and temperatures, being ruled by the competition between the body-centered-cubic (bcc) and face-centered-cubic (fcc) crystalline structures and the fluid phase. We confirm the existence of a reentrant bcc phase in the phase diagram of the Gaussian-core model, just above the triple point. We also trace the bcc-fcc coexistence line of the inverse-power-law model as a function of the power exponent n and relate the common features in the phase diagrams of such systems to the softness degree of the interaction. 相似文献
3.
P. Vitarelli S. Cavallaro R. Ottaná L. M. Saija N. Giordano 《Reaction Kinetics and Catalysis Letters》1984,25(1-2):79-82
The isomerization-disproportionation of m-xylene has been investigated over a series of dealuminated mordenites characterized by Si/Al ratios varying from 5 to 15. Catalytic activity increases with the Si/Al ratio and correspondingly also the products of disproportionation. This behavior is interpreted in terms of increasing acid strength leading to a higher activity and selectivity to disproportionation through a common mechanism which involves both a parallel and a consecutive route.
- - , Si/Al, 5 15. Si/Al, . , , , , .相似文献
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Antonina S. Alemasova Natalya V. Alemasova Alexander A. Pupyshev 《Central European Journal of Chemistry》2013,11(11):1852-1859
The theoretical approach for extractants selection during hyphenated atomic absorption determination of highly volatile metals (Pb, Cd), hydride- (Sb, Bi) and carbide-forming (Cr) metals using thermodynamic modelling was proposed. The calculated parameter — maximum pyrolysis temperature — can be used for selection of the extractants and chemical modifiers. Using this approach the antimony extract with Brilliant green was modified for which the 1.8-fold sensitivity and 2.6-fold repeatability decreasing while extract sampling in graphite furnace was observed. A chemical modifier — mixture of hydrazine nitrate with the palladium(II) complex with Xylenol orange — was theoretically selected and experimentally tested, which allowed to enhance the maximum pyrolysis temperature on 200°C, to eliminate extract matrix influence. Using this modifier two-fold increasing in sensitivity and 3-fold decreasing in relative standard deviation was achieved while extraction atomic absorption determination. 相似文献
6.
Antonina Moczulska 《Journal of carbohydrate chemistry》2013,32(8):1179-1192
Abstract Selective benzoylation of l-(β-d-xylopyranosyl)-3,5-dimethylpyrazole (1) has been performed to give 2,3,4-tri- (2), 3,4-di- (3), 2,4-di- (4), 3- (5) and 4-benzoate (6). The O-acetyl derivatives of compounds 3 and 4 (7, 8), di-O-acetyl of 5 and 6 (9, 10) and O-methanesulphonyl of 3 and 4 (11, 12) have been obtained. The relative reactivity of the hydroxyl groups of 1 was HO-4 ≥ HO-3 ? HO-2. The analysis of 1 H NMR and 13C NMR spectra of 1-12 is presented. 相似文献
7.
The Maximum Clique Problem (MCP) is regarded here as the maximization of an indefinite quadratic form over the canonical simplex. For solving MCP an algorithm based upon Global Optimality Conditions (GOC) is applied. Furthermore, each step of the algorithm is analytically investigated and tested. The computational results for the proposed algorithm are compared with other Global Search approaches. 相似文献
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Lukas Stolzer Antonina Vigovskaya Prof. Christopher Barner‐Kowollik Dr. Ljiljana Fruk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14309-14313
A photochemical approach based on nitrile imine‐mediated tetrazole‐ene cycloaddition is introduced to functionalize gold nanorods with biomolecules. For this purpose, a bifunctional, photoreactive linker containing thioctic acid as the Au anchoring group and a tetrazole moiety for the light‐induced reaction with maleimide‐capped DNA was prepared. The tetrazole‐based reaction on the nanoparticles’ surface results in a fluorescent pyrazoline product allowing for the spectroscopic monitoring of the reaction. This first example of nitrile imine‐mediated tetrazole‐ene cycloaddition (NITEC)‐mediated biofunctionalization of Au nanorods paves the way for the attachment of sensitive biomolecules, such as antibodies and other proteins, under mild conditions and expands the toolbox for the tailoring of nanomaterials. 相似文献