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841.
Irene Inoquio-Renteria Juan Rivera-Letelier 《Bulletin of the Brazilian Mathematical Society》2012,43(1):99-127
Consider a rational map f of degree at least 2 acting on its Julia set J(f), a H?lder continuous potential φ: J(f) → ℝ and the pressure P(f,φ). In the case where
supJ(f) f < P(f,f),\mathop {\sup }\limits_{J(f)} \phi < P(f,\phi ), 相似文献
842.
An analytical procedure was developed for the determination of some natural pesticides (piperonyl butoxide, nicotine, rotenone, spinosad, and abamectin B1a) in fruit matrixes. The quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was used for extraction. Analysis of the extract was performed by LC-electrospray ionization (ESI)-MS/MS. The ions prominent in the ESI spectra were [M+Na]+ for abamectin B1a, [M+NH4]+ for piperonyl butoxide, and [M+H]+ for the rest of the compounds. A Zorbax SB-C18 column was used with a programmed gradient mobile phase consisting of (A) water containing 0.1% formic acid and 5 mM ammonium formate, and (B) acetonitrile containing 2 mM sodium acetate. The method was linear within the investigated concentration range, displaying a calibration curve correlation factor of 0.99. The CVs obtained were below 20%, and recoveries were in the 70-110% range. 相似文献
843.
Lucas R Vengut-Climent E Gómez-Pinto I Aviñó A Eritja R González C Morales JC 《Chemical communications (Cambridge, England)》2012,48(24):2991-2993
Mono- and disaccharides have been shown to stack on top of DNA duplexes stabilizing sequences with terminal C-G base pairs. Here we present an apolar version of glucose and cellobiose as new capping agents that stack on DNA increasing considerably its stability with respect to their natural polyhydroxylated mono- and disaccharide DNA conjugates. 相似文献
844.
Irene Benedetti 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(4):2376-2377
In this paper, we define a topological index for compact multivalued maps in convex metrizable subsets of a locally convex topological vector space in order to correct the proofs of Theorems 4.1 and 4.2 in Benedetti et al. (2011) [1]. 相似文献
845.
846.
Two-dimensional x-ray grating interferometer 总被引:1,自引:0,他引:1
We report on the design and experimental realization of a 2D x-ray grating interferometer. We describe how this interferometer has been practically implemented, discuss its performance, and present multidirectional scattering (dark-field) maps and quantitative phase images that have been retrieved using this device. 相似文献
847.
We investigate the effect of anomalous field enhancement in metamaterials (MMs) where the effective refractive index gradually changes from positive to negative values, i.e., transition MMs. We demonstrate that considerable field enhancement can be achieved in lossy optical transition MMs that have electromagnetic material properties obtained from experimental data. The field enhancement factor is found to be polarization dependent and largely determined by the material parameters and the width of the transition layer. 相似文献
848.
Coin I Dölling R Krause E Bienert M Beyermann M Sferdean CD Carpino LA 《The Journal of organic chemistry》2006,71(16):6171-6177
The depsipeptide technique is a recently developed method for peptide synthesis which is applicable to difficult sequences when the synthetic difficulty arises because of aggregation phenomena. In the present work, application of the depsipeptide method to extremely difficult sequences has been demonstrated and a serious side reaction involving diketopiperazine formation uncovered and subsequently avoided by the appropriate use of the Bsmoc protecting group. Many other aspects of the technique have been investigated, such as the stability of the depsi units during assembly and workup procedures, the completeness of the O-acylation step, the occurrence of epimerization of the amino acid activated during O-acylation, and the nature of side products formed. In addition, the method was modified so as to allow for completely automated syntheses of long-chain depsipeptides without the need for any interruption by manual esterification procedures. Finally, the synthesis efficiency of the new depsipeptide technique was shown to be comparable to that of the well-known pseudoproline technique. 相似文献
849.
Fabrizio Colombo Irene Sabadini Frank Sommen 《Mathematical Methods in the Applied Sciences》2010,33(17):2050-2066
In this paper we show a version of the Fueter mapping theorem that can be stated in integral form based on the Cauchy formulas for slice monogenic (or slice regular) functions. More precisely, given a holomorphic function f of a paravector variable, we generate a monogenic function by an integral transform whose kernel is particularly simple. This procedure allows us to define a functional calculus for n‐tuples of commuting operators (called ?‐functional calculus) based on a new notion of spectrum, called ?‐spectrum, for the n‐tuples of operators. Analogous results are shown for the quaternionic version of the theory and for the related ?‐functional calculus. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
850.
ThomasD. Schladt MohammedIbrahim Shukoor Kerstin Schneider MuhammadNawaz Tahir Filipe Natalio Irene Ament Jan Becker FlorianD. Jochum Stefan Weber Oskar Khler Patrick Theato LauraMaria Schreiber Carsten Snnichsen HeinzC. Schrder WernerE.G. Müller Wolfgang Tremel 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2010,122(23):4068-4072
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