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101.
Antonios D. Melas 《Journal d'Analyse Mathématique》2000,82(1):1-20
In this paper, we study the growth of universal functions (Taylor series) on the unit discD. We describe a class of growth types prohibited for such a function. By investigating the relation between growth and value
distribution, we prove that every universal function assumes every complex value, with at most one exception, on sequences
inD that approach ϖD rather slowly. We use this to get a large class of equations, including polynomials with Nevanlinna coefficients and equations
of iterates, that no universal function satisfies. Finally, we produce a universal function whose growth is bounded by
, which is close to the rates of growth prohibited.
The author would like to thank the referee for suggesting references [3] and [4]. 相似文献
102.
Antonios D. Melas 《Proceedings of the American Mathematical Society》2003,131(2):631-636
Let be the th Dirichlet eigenvalue of a bounded domain in . According to Weyl's asymptotic formula we have
The optimal in view of this asymptotic relation lower estimate for the sums has been proven by P.Li and S.T.Yau (Comm. Math. Phys. 88 (1983), 309-318). Here we will improve this estimate by adding to its right-hand side a term of the order of that depends on the ratio of the volume to the moment of inertia of .
The optimal in view of this asymptotic relation lower estimate for the sums has been proven by P.Li and S.T.Yau (Comm. Math. Phys. 88 (1983), 309-318). Here we will improve this estimate by adding to its right-hand side a term of the order of that depends on the ratio of the volume to the moment of inertia of .
103.
Applied Biochemistry and Biotechnology - The 71 poster papers presented at the 16th Symposium on Biotechnology for Fuels and Chemicals provided new information on ethanol production, feedstock... 相似文献
104.
We consider a six-dimensional Einstein–Maxwell system compactified in an axisymmetric two-dimensional space with one capped regularized conical brane of codimension one. We study the cosmological evolution which is induced on the regularized brane as it moves in between known static bulk and cap solutions. Looking at the resulting Friedmann equation, we see that the brane cosmology at high energies is dominated by a five-dimensional ρ2 energy density term. At low energies, we obtain a Friedmann equation with a term linear to the energy density with, however, negative coefficient in the small four-brane radius limit (i.e., with negative effective Newton's constant). We discuss ways out of this problem. 相似文献
105.
Alexei Plotnikov Carla Vogt Klaus Wetzig Antonios Kyriakopoulos 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
This paper represents a further development of the theoretical basis for the interpretation of transient data obtained by scanning laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to overcome the non-linear distortion of the transient signal as well as to improve spatial resolution. The reconstruction of the relative concentration profile from transient data is suggested in terms of simple models of analytical information gathering for extreme cases of depth distribution of the analyte. The main attention is focused on the geometry of the overlap between the laser spot and the concentration profile, the consideration of which allows defining explicitly the response function necessary for the deconvolution procedure. The profile of the transient signal simulated according the proposed model for a real system (copper conductor lines in polymer matrix) is in good agreement with the measured data. The feasibility of the deconvolution procedure to reconstruct the relative concentration profile for a model system is demonstrated. The suggested analytical framework is intended to overcome certain limitations of scanning LA-ICP-MS which are caused by the measuring process independently from the optimization of hardware and experimental conditions. 相似文献
106.
Karakostas N Naumov S Siskos MG Zarkadis AK Hermann R Brede O 《The journal of physical chemistry. A》2005,109(51):11679-11686
Parent radical cations of nonpolar solvents (alkanes and alkyl chlorides) ionize 9-(trimethylsilyl)xanthenes and 9-(trimethylsilyl)fluorenes in a diffusion-controlled electron transfer. The actual electron jump as the deciding part of the process does not require a defined encounter complex, and therefore the reactants are not subjected to any geometry optimization. Considering the molecule dynamics of the donors, bending motions of the silyl group are concerted with fluctuations of the highest occupied molecular orbital electrons. Ionizing such a standing conformer mixture creates metastable (microsecond) as well as dissociative donor radical cations. A mobility restriction of the benzylic silane group in positions vertical to the phenyl plane stabilizes the radical cations and accounts for a declining amount of dissociative radical cations, which undergo C-Si bond fragmentation in the order benzylsilane > xanthenylsilane > fluorenylsilane. 相似文献
107.
Pascal Cauliez Dominique Fasseur Daniel Couturier BenoÏT Rigo Antonios Kolocouris 《Journal of heterocyclic chemistry》1996,33(4):1233-1237
The carbamoylation of some lactams derivatived from pyroglutamic acid as been studied; better yields were obtained starting from the unsubstitued lactam (toluene, 80°) rather than starting with the N-silyllactam (room temperature), although these latter reaction conditions could be interesting for heat sensitive compounds. Methyl and phenyl isothiocyanate react only with the sodium salt of methyl pyroglutamate, giving 1,5-diaddition products. 相似文献
108.
BenoÎT Rigo Antonios Kolokouris Nicolas Kolokouris 《Journal of heterocyclic chemistry》1995,32(5):1489-1492
Starting from readily available pyroglutamic acid 1 , some N-fatty acylpyroglutamic acids were synthesized and characterized by their spectral data. A preliminary pharmacological study showed that N-stearoylpyroglutamic acid 4c displays a CNS stimulating effect on mice. 相似文献
109.
Applied Biochemistry and Biotechnology - 相似文献
110.
Ashcroft JM Gu W Zhang T Hughes SM Hartman KB Hofmann C Kanaras AG Kilcoyne DA Le Gros M Yin Y Alivisatos AP Larabell CA 《Chemical communications (Cambridge, England)》2008,(21):2471-2473
This communication reports the development of a TiO2-streptavidin nanoconjugate as a new biological label for X-ray bio-imaging applications; this new probe, used in conjunction with the nanogold probe, will make it possible to obtain quantitative, high-resolution information about the location of proteins using X-ray microscopy. 相似文献