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111.
112.
Wladimir de Azevedo Pribitkin 《Journal of Number Theory》2011,131(11):2047-2060
We establish the oscillatory behavior of several significant classes of arithmetic functions that arise (at least presumably) in the study of automorphic forms. Specifically, we examine general L-functions conjectured to satisfy the Grand Riemann Hypothesis, Dirichlet series associated with classical entire forms of real weight and multiplier system, Rankin-Selberg convolutions (both “naive” and “modified”), and spinor zeta-functions of Hecke eigenforms on the Siegel modular group of genus two. For the second class we extend results obtained previously and jointly by M. Knopp, W. Kohnen, and the author, whereas for the fourth class we provide a new proof of a relatively recent result of W. Kohnen. 相似文献
113.
The crystallization patterns induced by nano- and picosecond laser pulses within an amorphous matrix, with various degrees of relaxation, present morphological instabilities. We show by TEM observations that the final crystalline structures of the relaxed amorphous state, after nanosecond laser excitation, and the “as-deposited” amorphous state after picosecond excitation, present similar morphology. Structurally, metastable crystalline states have been formed under laser irradiation. A probable process for these instabilities is related to competition between the light-induced electronic excitation and thermal processes during the nucleation stage. 相似文献
114.
We consider mixtures of compressible viscous fluids consisting of two miscible species. In contrast to the theory of non-homogeneous
incompressible fluids where one has only one velocity field, here we have two densities and two velocity fields assigned to
each species of the fluid. We obtain global classical solutions for quasi-stationary Stokes-like system with interaction term.
This work was supported by SFB 611. 相似文献
115.
Ohne Zusammenfassung 相似文献
116.
Xavier?CarvajalEmail author Wladimir?Neves 《Integral Equations and Operator Theory》2012,72(2):179-195
In this paper we study the theory of operators on complex Hilbert spaces, which achieve the norm in the unit sphere. We prove
important results concerning the characterization of the AN{\mathcal{AN} } operators, see Definition 1.2. The class of the AN{\mathcal{AN}} operators contains the algebra of the compact ones. 相似文献
117.
Combination of sugar analysis and stable isotope ratio mass spectrometry to detect the use of artificial sugars in royal jelly production 总被引:1,自引:0,他引:1
Marine Wytrychowski Ga?lle Daniele Hervé Casabianca 《Analytical and bioanalytical chemistry》2012,403(5):1451-1456
The effects of feeding bees artificial sugars and/or proteins on the sugar compositions and 13C isotopic measurements of royal jellies (RJs) were evaluated. The sugars fed to the bees were two C4 sugars (cane sugar and
maize hydrolysate), two C3 sugars (sugar beet, cereal starch hydrolysate), and honey. The proteins fed to them were pollen,
soybean, and yeast powder proteins. To evaluate the influence of the sugar and/or protein feeding over time, samples were
collected during six consecutive harvests. 13C isotopic ratio measurements of natural RJs gave values of around −25 ‰, which were also seen for RJs obtained when the bees
were fed honey or C3 sugars. However, the RJs obtained when the bees were fed cane sugar or corn hydrolysate (regardless of
whether they were also fed proteins) gave values of up to −17 ‰. Sugar content analysis revealed that the composition of maltose,
maltotriose, sucrose, and erlose varied significantly over time in accordance with the composition of the syrup fed to the
bees. When corn and cereal starch hydrolysates were fed to the bees, the maltose and maltotriose contents of the RJs increased
up to 5.0 and 1.3 %, respectively, compared to the levels seen in authentic samples (i.e., samples obtained when the bees
were fed natural food: honey and pollen) that were inferior to 0.2% and not detected, respectively. The sucrose and erlose
contents of natural RJs were around 0.2 %, whereas those in RJs obtained when the bees were fed cane or beet sugar were as
much as 4.0 and 1.3 %, respectively. The combination of sugar analysis and 13C isotopic ratio measurements represents a very efficient analytical methodology for detecting (from early harvests onward)
the use of C4 and C3 artificial sugars in the production of RJ. 相似文献
118.
Lluveras-Tenorio A Andreotti A Bonaduce I Boularand S Cotte M Roqué J Colombini MP Vendrell-Saz M 《Chemistry Central journal》2012,6(1):45-18
ABSTRACT: BACKGROUND: Establishing the distribution of materials in paintings and that of their degradation products by imaging techniques is fundamental to understand the painting technique and can improve our knowledge on the conservation status of the painting. The combined use of chromatographic-mass spectrometric techniques, such as GC/MS or Py/GC/MS, and the chemical mapping of functional groups by imaging SR FTIR in transmission mode on thin sections and SR XRD line scans will be presented as a suitable approach to have a detailed characterisation of the materials in a paint sample, assuring their localisation in the sample build-up. This analytical approach has been used to study samples from Catalan paintings by Josep Maria Sert y Badia (20th century), a muralist achieving international recognition whose canvases adorned international buildings. RESULTS: The pigments used by the painter as well as the organic materials used as binders and varnishes could be identified by means of conventional techniques. The distribution of these materials by means of Synchrotron Radiation based techniques allowed to establish the mixtures used by the painter depending on the purpose. CONCLUSIONS: Results show the suitability of the combined use of SR FTIR and SR XRD mapping and conventional techniques to unequivocally identify all the materials present in the sample and their localization in the sample build-up. This kind of approach becomes indispensable to solve the challenge of micro heterogeneous samples. The complementary interpretation of the data obtained with all the different techniques allowed the characterization of both organic and inorganic materials in the samples layer by layer as well as to establish the painting techniques used by Sert in the works-of-art under study. 相似文献
119.
Maldonado A López-Esparza R Ober R Gulik-Krzywicki T Urbach W Williams CE 《Journal of colloid and interface science》2006,296(1):365-369
We have studied the effect of adding a water-soluble polymers (PEG) to the lamellar phases of the ternary system tetradecyldimethylaminoxide (C14DMAO)-hexanol-water. The results of Freeze-Fracture Electron Microscopy (FFEM) and Small Angle X-ray Scattering (SAXS) experiments show that the addition of the polymer induces the spontaneous formation of highly monodisperse multilayered vesicles above a threshold polymer concentration. 相似文献
120.
Hong Bing LIU Cheng Bin CUI * Bing CAI Qian Qun GU Dong Yun ZHANG Qing Chun ZHAO Hua Shi GUAN Key Laboratory of Marine Drugs Ministry of Education China Marine Drug Food Institute Ocean University of China Qingdao Tianjin Institute for Biomedicinal Research 《中国化学快报》2005,16(2):215-218
Pterocarya tonkinesis(Franch.)Dode.(Juglandaceae)forms a typical community ofriverside season rain forest in Xishuangbanna area of Yunnan province1.The same genusplant P.stenoptera C.DC.,has long been used as a traditional Chinese herbal medicine2and P.tonkinesis,itself,is also used as a folk medicine for the treatment of certain cancersin partial area of China.However,no report had so far been seen on the chemicalconstituents and their biological activities of the title plant yet.In the … 相似文献