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131.
The rate of a standard gradedK-algebraR is a measure of the growth of the shifts in a minimal free resolution ofK as anR-module. It is known that rate(R)=1 if and only ifR is Koszul and that rate(R) ≥m(I)−1 wherem(I) denotes the highest degree of a generator of the defining idealI ofR. We show that the rate of the coordinate ring of certain sets of pointsX of the projective space P
n
is equal tom(I)−1. This extends a theorem of Kempf. We study also the rate of algebras defined by a space of forms of some fixed degreed and of small codimension. 相似文献
132.
133.
D. Bazzacco F. Brandoline K. Löwenich P. Pavan C. Rossi Alvarez M. De Poli A. M. I. Haque 《Hyperfine Interactions》1990,59(1-4):129-132
The g-factor of the first 2+ state in198Hg,200Hg and202Hg has been measured using the thin foil Transient Field technique. The values were calibrated to the known g-factor of the
first 5/2− state in199Hg. The levels were Coulomb excited by 217 MeV nickel ions with gadolinium acting as ferromagnetic medium. The obtained values
are rather constant and contradict a previously observed dip at200Hg. Two other g-factors have been remeasured in199Hg. 相似文献
134.
Ohne ZusammenfassungAus dem Italienischen übersetzt von J. Matula (Wien). 相似文献
135.
136.
This paper is devoted to the analysis of a one-dimensional model for phase transition phenomena in thermoviscoelastic materials.
The corresponding parabolic-hyperbolic PDE system features a strongly nonlinear internal energy balance equation, governing the evolution of the absolute temperature ϑ, an evolution equation for the phase change parameter χ, including constraints on the phase variable, and a hyperbolic stress-strain relation for the displacement variable u. The main novelty of the model is that the equations for χ and u are coupled in such a way as to take into account the fact that the properties of the viscous and of the elastic parts influence
the phase transition phenomenon in different ways. However, this brings about an elliptic degeneracy in the equation for u which needs to be carefully handled.
First, we prove a global well-posedness result for the related initial-boundary value problem. Secondly, we address the long-time
behavior of the solutions in a simplified situation. We prove that the ω-limit set of the solution trajectories is nonempty, connected and compact in a suitable topology, and that its elements solve
the steady state system associated with the evolution problem.
Dedicated to Jürgen Sprekels on the occasion of his 60th birthday 相似文献
137.
J. -P. Leroy J. Micholi G. -C. Rossi 《Zeitschrift fur Physik C Particles and Fields》1987,36(2):305-310
We prove that a complete fixing of the temporal gauge,A o =0, in which one imposesa subsidiary gauge condition, such as, for instance ?i A i (x,t 0) = 0 leads to consistent formulation of the theory with simple Feynman rulesand a well defined gluon propagator. The correct exponentiation of the time dependence of the Wilson loop has been checked to occur up to order g4. 相似文献
138.
Torres MF Sales PS de Rossi RH Fernández MA 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):17858-17866
The mixed system of a nonionic hydrocarbon surfactant, polyoxyethylene (23) lauryl ether (Brij-35), and a perfluorinated surfactant, perfluorononanoic acid, was investigated by a combination of methods. The critical micelle concentrations (cmc's) have been determined over a wide range of sample compositions by fluorescence and UV-visible spectrophotometry using pyrene and N-(4-nitrophenyl) perfluorononanamide, respectively, as molecular probes. The values of the cmc's obtained were considerably different with the two techniques employed. Measurements of the (19)F nuclear magnetic resonance chemical shift of the same mixtures showed two breaks in the plots of Δδ(f) versus molar fraction of the perfluorinated surfactant. Conductivity and surface tension measurements also showed two breaks. The behavior is attributed to the formation of mixed micelles that change their composition when the fraction of the fluorinated compound increases and some segregation of the fluorinated compound takes place at a high total surfactant concentration. 相似文献
139.
G. Ciasca M. Chiarpotto G. Campi B. Bocca M. Rodio A. Pino A. Ricci N. Poccia C. Rossi A. Alimonti H. Amenitsch P. De Sole A. Bianconi 《Journal of nanoparticle research》2011,13(11):6149-6155
This study investigates the uptake of iron and aluminium by apoferritin. In particular, we provide the first evidence that apoferritin is able to bind in vitro the physiological form of aluminium, Al(OH)4 ?, to reach an Al/Fe atomic ratio of about 0.15. Mass spectrometry analysis shows that the Al content increases linearly as a function of Al concentration in solution. These findings provide a better understanding of the Al uptake in vivo, confirming that the metal content of ferritin depends on the metal bio-availability. 相似文献
140.
M. Anselmino H. Avakian D. Boer F. Bradamante M. Burkardt J. P. Chen E. Cisbani M. Contalbrigo D. Crabb D. Dutta L. Gamberg H. Gao D. Hasch J. Huang M. Huang Z. Kang C. Keppel G. Laskaris Z. -T. Liang M. X. Liu N. Makins R. D. Mckeown A. Metz Z. -E. Meziani B. Musch J. -C. Peng A. Prokudin X. Qian Y. Qiang J. W. Qiu P. Rossi P. Schweitzer J. Soffer V. Sulkosky Y. Wang B. Xiao Q. Ye Q. -J. Ye F. Yuan X. Zhan Y. Zhang W. Zheng J. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2011,47(3):1-21