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91.
Wieslaw M. Cholody Jerzy Konopa Ippolito Antonini Sante Martelli 《Journal of heterocyclic chemistry》1991,28(2):209-214
A convenient method for the synthesis of unsubstituted and substituted 1-amino-9-imino-4-nitro-9,10-dihydroacridines, 9 and 10 , respectively, is reported. Their 1H nmr data are reported and discussed in order to confirm the imino tautomeric structure. 相似文献
92.
We experimentally study light self-trapping in triangular photonic lattices induced optically in nonlinear photorefractive crystals. We observe the formation of two-dimensional discrete and gap spatial solitons originating from the first and second bands of the linear transmission spectrum. 相似文献
93.
Electronic Olfactory Sensor Based on A. mellifera Odorant‐Binding Protein 14 on a Reduced Graphene Oxide Field‐Effect Transistor
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Dr. Melanie Larisika Caroline Kotlowski Christoph Steininger Rosa Mastrogiacomo Prof. Paolo Pelosi Prof. Stefan Schütz Serban F. Peteu Prof. Christoph Kleber Ciril Reiner‐Rozman Dr. Christoph Nowak Prof. Wolfgang Knoll 《Angewandte Chemie (International ed. in English)》2015,54(45):13245-13248
An olfactory biosensor based on a reduced graphene oxide (rGO) field‐effect transistor (FET), functionalized by the odorant‐binding protein 14 (OBP14) from the honey bee (Apis mellifera) has been designed for the in situ and real‐time monitoring of a broad spectrum of odorants in aqueous solutions known to be attractants for bees. The electrical measurements of the binding of all tested odorants are shown to follow the Langmuir model for ligand–receptor interactions. The results demonstrate that OBP14 is able to bind odorants even after immobilization on rGO and can discriminate between ligands binding within a range of dissociation constants from Kd=4 μM to Kd=3.3 mM . The strongest ligands, such as homovanillic acid, eugenol, and methyl vanillate all contain a hydroxy group which is apparently important for the strong interaction with the protein. 相似文献
94.
In a recent paper (Appl. Math. Comput. 215:1622–1645, 2009), the authors proposed a method of summation of some slowly convergent series. The purpose of this note is to give more theoretical analysis for this transformation, including the convergence acceleration theorem in the case of summation of generalized hypergeometric series. Some new theoretical results and illustrative numerical examples are given. 相似文献
95.
We study Riesz and Bessel potentials in the settings of Hankel transform, modified Hankel transform and Hankel-Dunkl transform. We prove sharp or qualitatively sharp pointwise estimates of the corresponding potential kernels. Then we characterize those 1 ≤ p, q≤∞, for which the potential operators satisfy L p -L q estimates. In case of the Riesz potentials, we also characterize those 1 ≤ p, q ≤ ∞, for which two-weight L p -L q estimates, with power weights involved, hold. As a special case of our results, we obtain a full characterization of two power-weight L p -L q bounds for the classical Riesz potentials in the radial case. This complements an old result of Rubin and its recent reinvestigations by De Nápoli, Drelichman and Durán, and Duoandikoetxea. 相似文献
96.
We present an abstract characterization of various types of Menger algebras of n-place functions allowing certain permutations of variables. 相似文献
97.
M. Nowak 《Rheologica Acta》1998,37(4):336-344
The results of an experimental investigation of the flow of a highly dilute cationic surfactant solution (tetradecyl trimethyl
ammonium bromide with added sodium salicylate as counterion, equimolar 2.4mM) around a rotating sphere are presented. The
flow and the shear-induced phase transition are visualized by means of a Toepler Schlieren optics. The buildup of the shear-induced
structures occurs only above a critical shear rate. Once this critical value is exceeded the shear-induced phase separation
starts after a characteristic deformation with the shear rate reduced by the critical one. Further analysis of the obtained
data is performed on basis of an analytical calculation of the flow around a rotating sphere in a second order fluid (Thomas
and Walters, 1964; Giesekus, 1965). From some characteristic features of the shear-induced structures as induction time and
position the parameter describing the elastic properties of the fluid is estimated.
Received: 6 January 1998 Accepted: 1 May 1998 相似文献
98.
Based on a very precise approximation to the lattice discrepancy of a Lamé disc, an asymptotic formula is established for the number of lattice points in the three-dimensional body $$|u_1|^{mk}+\left(|u_2|^k+|u_3|^k\right)^{m}\le x^{mk},$$ for large real x and fixed reals m, k. Particular attention is paid to the boundary points of Gaussian curvature zero. 相似文献
99.
Quan Shi Narendiran Vitchuli Joshua Nowak Jane M. Caldwell Frederick Breidt Mohamed Bourham Xiangwu Zhang Marian McCord 《European Polymer Journal》2011,(7):1402-1409
Durable antibacterial Ag/polyacrylonitrile (Ag/PAN) hybrid nanofibers were prepared by atmospheric plasma treatment and electrospinning. Atmospheric helium plasma treatment was first used to reduce the AgNO3 precursor in pre-electrospinning solutions into metallic silver nanoparticles, followed by electrospinning into continuous and smooth nanofibers with Ag nanoparticles embedded in the matrix. SEM, TEM, and EDX spectra were used to study the structure and surface elemental composition of the nanofibers. Silver nanoparticles, with diameters ranging between 3 and 6 nm, were found to be uniformly dispersed in the nanofiber matrix. The Ag/PAN nanofibers exhibited slow and long-lasting silver ion release, which provided robust antibacterial activity against both Gram-positive Bacillus cereus and Gram-negative Escherichia coli microorganisms. 相似文献
100.
This article presents the investigation results of the polarized IR spectra of the hydrogen bond in N-phenylacrylamide crystals measured in the frequency range of the proton and deuteron, ν(N-H) and ν(N-D), stretching vibration bands. The basic spectral properties of the crystals were interpreted quantitatively in terms of the "strong-coupling" theory. The proposed model of the centrosymmetric dimer of hydrogen bonds facilitated the explanation of the well-developed, two-branch structure of the ν(N-H) and ν(N-D) bands as well as the isotopic dilution effects in the spectra. The vibronic mechanism of the generation of the long-wave branch of the ν(N-H) band ascribed to the excitation of the totally symmetric proton vibration was elucidated. The complex fine structure pattern of ν(N-H) and ν(N-D) bands in N-phenylacrylamide spectra in comparison with the spectra of other secondary amide crystals (e.g., N-methylacetamide and acetanilide) can be accounted for in terms of the vibronic model for the forbidden transition breaking in the dimers. On the basis of the linear dichroic and temperature effects in the polarized IR spectra of N-phenylacrylamide crystals, the H/D isotopic "self-organization" effects were revealed. 相似文献