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991.
将Phelps引理,Ekland变分原理,Pareto有效性定理推广到拓扑线性空间,同时证明了这三个定理与郑喜印证明的拓扑线性空间中的Drop定理彼此等价. 相似文献
992.
J. J. Zwinselman N. M. M. Nibbering J. van der Greef M. C. Ten Noever De Brauw 《Journal of mass spectrometry : JMS》1983,18(12):525-529
The positive ion field desorption (FD) spectrum of arginine taken at the best anode temperature only contains a peak due to [M+H]+ ions. At higher emitter temperatures a considerable amount of fragmentation is induced and the [M+H NH3]+ ions become most abundant. Specific 15N labelling reveals that the eliminated ammonia molecule, exclusively, contains one of the terminal nitrogen atoms of the guanidyl group. This also applies to the ammonia loss from metastably decomposing [M+H]+ ions. The positive ion fast atom bombardment (FAB) spectrum shows more fragmentation than the FD spectrum. In contrast with the FD results, the [M+H]+ ions generated upon FAB with ion lifetimes <10−6 s eliminate both ammonia containing one of the terminal nitrogen atoms of the guanidyl group and ammonia containing the α-amino group in the ratio of 1.35, as found by 15N labelling. The metastably decomposing [M+H]+ ions, however, eliminate only the former ammonia molecule. In the negative ion FD and FAB spectra no other peak than that corresponding to the [M H]− ion is observed. Some attention has been paid to the thermal degradation of arginine on the basis of a few Curie-point pyrolysis experiments. 相似文献
993.
Possible techniques for generating supersaturation, which could be applied to precipitation of barium chromate from aqueous solution, are reviewed, and experimental work carried out to examine the feasibility of the more promising of these techniques are described. The process requirements of a reasonable rate of production of relatively large (∼ 100 μm) crystals of normal habit, are shown to be satisfied by the technique of precipitation from homogeneous solution (PFHS), employing urea hydrolysis to cause a controlled change in the solubility of barium chromate in an acidic aqueous medium. Some recent experimental work on urea hydrolysis, as applied to the precipitation of barium chromate, has been reanalysed and found to be in agreement with the generally accepted, pseudo-first order reaction model. The effects of urea hydrolysis on the precipitation process are discussed. 相似文献
994.
This paper is devoted to a constructiveand critical analysis of the structure of certain dynamical systems from a group manifold point of view recently developed. This approach is especially suitable for discussing the structure of the quantum theory, the classical limit, the Hamilton-Jacobi theory and other problems such as the definition and globalization of the Poincaré-Cartan form which appears in the variational approach to higher order dynamical systems. At the same time, i t opens a way for the classification of all hamiltonian and lagrangian systems associated with suitably defined dynamical groups. Both classical and quantum dynamics are discussed, and examples of all the different structures appearingin the theory are provided, including a treatment of constrained and generalized higher order dynamical systems. 相似文献
995.
Y. De Decker F. Baras 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,78(2):173-186
We study the dynamics of a class of catalytic surface
reactions in which an adsorbed molecule undergoes dissociation giving oxygen,
which then rapidly reacts with H adatoms to give water.
The reaction-diffusion equations predict bistability and explosive
transients similar to those observed in several low-pressure experiments.
Kinetic Monte Carlo simulations reveal however that the
dynamics can be strongly affected by spontaneous, inhomogeneous
fluctuations of composition on the surface. In particular,
bifurcation points can be displaced and the explosive character
of the transients can be lost, depending on a subtle balance between
the rate of reaction and the mobility of the decomposing species.
These effects can be quantified on the basis of
a stochastic formulation of the dynamics taking into account
spatial correlations.
This approach allows to better delimit
the applicability of the traditional
reaction-diffusion modelling in the case of reactions such as
the reduction of NO
x
or SO
x
species on catalytic surfaces. 相似文献
996.
A. Akindinov A. Alici P. Antonioli S. Arcelli M. Basile F. Bellini D. Caffarri G. Cara Romeo L. Cifarelli F. Cindolo A. De Caro D. De Gruttola S. De Pasquale K. Doroud M. Fusco Girard B. Guerzoni D. Hatzifotiadou W. W. Jung D. W. Kim J. S. Kim S. Kiselev G. Laurenti K. Lee S. C. Lee D. Malkevich A. Margotti R. Nania A. Nedosekin F. Noferini P. Pagano A. Pesci O. Pinazza R. Preghenella M. Ryabinin E. Scapparone G. Scioli J. Seo A. Silenzi K. Voloshin M. C. S. Williams C. Zampolli A. Zichichi 《The European Physical Journal C - Particles and Fields》2010,68(3-4):601-607
The Time-Of-Flight detector (TOF) of the ALICE experiment at the CERN LHC is based on Multi-gap Resistive Plate Chambers (MRPCs). The TOF detector consists of 152928 readout channels covering a total area of 141 m2. In this paper the results of the calibration with cosmic-ray data collected during 2009 are presented. 相似文献
997.
S. Capozziello R. Cianci M. De Laurentis S. Vignolo 《The European Physical Journal C - Particles and Fields》2010,70(1-2):341-349
We discuss the emergence of scalar gravitational waves in metric-affine f(R)-gravity. Such a component allows to discriminate between metric and metric-affine theories The intrinsic meaning of this result is that the geodesic structure of the theory can be discriminated. We extend the formalism of cross-correlation analysis, including the additional polarization mode, and calculate the detectable energy density of the spectrum for cosmological relic gravitons. The possible detection of the signal is discussed against the sensitivities of the VIRGO, LIGO and LISA interferometers. 相似文献
998.
Richard De la cruz Juan Galvis Juan Carlos Juajibioy Leonardo Rendón 《Bulletin of the Brazilian Mathematical Society》2016,47(1):277-290
We study the one-dimensional Riemann problem for a hyperbolic system of three conservation laws of Temple class. The system is a simplification of a recently proposed system of five conservations laws by Bouchut and Boyaval that models viscoelastic fluids. An important issue is that the considered 3×3 system is such that every characteristic field is linearly degenerate. We study theRiemann problemfor this system and under suitable generalized Rankine-Hugoniot relation and entropy condition, both existence and uniqueness of particular delta shock type solutions are established. 相似文献
999.
ABSTRACTThis article summarises recent advances made in our laboratory towards the development of new technological applications, such as biosensors and organic light-emitting diodes (OLEDs) based on liquid crystals (LCs) other than LC displays. The study of biomolecular interaction using LC material relies on the specific interaction between the LC and the biomolecule of interest at interfaces that permit the biomolecular events to be amplified into easily measured signals for various sensing applications. In the first part, we emphases recent studies in the design and modulation of LC-based interfaces based on robust colloidal LC gels for biological amplification, qualitative and quantitative understanding of important biomolecular interactions at LC–aqueous interfaces for diagnostic and laboratory applications and design of LC droplets that hold promise to act as a marker for cells and cell-based interactions. In the second part, we described design of organic materials for application in OLEDs on various discotic monomers, dimers and oligomers. These molecules have the ability to transport charges, holes and electrons. In addition, because of the high conductivity and π–π stacking, they are considered as the advanced materials for practical applications. The technological advances in our laboratory using discotic LCs will be briefly presented in this article. 相似文献
1000.
Dayanne Cristiane Mozaner Bordin Marcela Nogueira Rabelo Alves Eduardo Geraldo de Campos Bruno Spinosa De Martinis 《Journal of separation science》2016,39(6):1168-1172
Disposable pipette tips extraction consists of a solid‐phase extraction in which the sorbent is poorly dispersed in a pipette tip, which allows a quick and dynamic contact between the aspirated analyte from the sample and the solid phase. It is a technique used particularly in food and forensic analysis, since it requires a small amount of sample and solvent. This article highlights the principles, advantages and disadvantages of the disposable pipette tips extraction method and reviews recent applications. 相似文献