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901.
Let 𝕂 be an algebraically closed field. We classify the finite groups having exactly one irreducible 𝕂-representation of degree bigger than one. The case where the characteristic of 𝕂 is zero, was done by G. Seitz in 1968. 相似文献
902.
Josephine McAndrew Stephan Paul Ralf Emmerich Ralf Engels Peter Fierlinger Mirko Gabriel Erwin Gutsmiedl Johannes Mellenthin Johannes Sch?n Wolfgang Schott Andreas Ulrich Florian Grüenauer Anton R?hrmoser 《Hyperfine Interactions》2012,207(1-3):13-17
Frozen solution samples were made from gold chloride and KAu(CN)2 solvated with TBP/xylene. The 197Au M?ssbauer parameters were similar to those same species as frozen solutions or adsorbed onto activated carbon. Solvated samples from EuO dissolved in HCl or H2SO4 and frozen gave characteristic Eu(III) spectra. All the spectra were consistent with bonding to the TBP being through hydronium ions or water molecules. 相似文献
903.
Lenagh-Snow GM Araújo N Jenkinson SF Martínez RF Shimada Y Yu CY Kato A Fleet GW 《Organic letters》2012,14(8):2142-2145
Primary amines with either 3,5-di-O-ditriflates of α-furanosides or 2,4-di-O-triflates of β-pyranosides form bicyclic azetidines in high yield. 相似文献
904.
This works extends the recent study on the dielectric permittivity of crystals within the Hartree model [E. Cancès, M. Lewin, Arch. Ration. Mech. Anal. 197 (1) (2010) 139–177] to the time-dependent setting. In particular, we prove the existence and uniqueness of the nonlinear Hartree dynamics (also called the random phase approximation in the physics literature), in a suitable functional space allowing to describe a local defect embedded in a perfect crystal. We also give a rigorous mathematical definition of the microscopic frequency-dependent polarization matrix, and derive the macroscopic Maxwell–Gauss equation for insulating and semiconducting crystals, from a first order approximation of the nonlinear Hartree model, by means of homogenization arguments. 相似文献
905.
906.
Martinez-Niconoff G Munoz-Lopez J Silva-Barranco J Carbajal-Domínguez A Martínez-Vara P 《Optics letters》2012,37(11):2121-2123
In this Letter, we describe the optical field associated with transmittances characterized by a slit-shaped curve. The influence of the curvature is that the diffraction field generates focusing regions. The focusing geometry corresponds to the geometry of the transmittance curve, except for scaling, rotations or translations. A relevant point is that the changes in the morphology of the diffraction field are bounded by the focusing regions. Our experimental and computational results are in good agreement with the theoretical predictions. 相似文献
907.
We present a method for phase retrieval in off-axis interferometric systems. By numerically calculating the transverse 1st and 2nd order derivatives of the interferogram, we show that one can directly retrieve the quantitative phase image, without the need for Fourier or Hilbert transformations. Because of this, the method is significantly faster than the current approaches. We illustrate our method using biological specimen data from three different off-axis quantitative phase imaging techniques. 相似文献
908.
Gabriel AA 《Ultrasonics sonochemistry》2012,19(2):346-351
The study determined the efficacy of Dynashock wave power ultrasound as an alternative processing technique for apple juice against a number of pathogenic and spoilage microorganisms. The effects of several implicit, intrinsic and extrinsic properties on the Dynashock wave inactivation of the microorganisms were also investigated. Results showed that acid adaptation increased the resistance of Escherichia coli O157:H7 and Salmonella spp. but decreased that of Listeria monocytogenes. Spoilage yeast mixed inoculum composed of Debaryomyces hansenii, Torulaspora delbrueckii, Clavispora lusitaniae, Pichia fermentans and Saccharomyces cerevisiae was found to be more resistant than any of the adapted or non-adapted pathogens. Among the individual, acid-adapted E. coli O157:H7, the MN-28 isolate was found most resistant; while three other individual isolates had greater resistance than the composited E. coli inoculum. Increased in pulp content decreased the efficacy of Dynashock waves, but co-treatment with ultraviolet-C rays significantly enhanced inactivation in the cloudy apple juice. The results demonstrated the potential of Dynashock wave technology, together with other antimicrobial hurdles as alternative juice processing technique/s. 相似文献
909.
Gabriel NAVARRO 《Frontiers of Mathematics in China》2013,8(5):1157-1183
We describe the valued Gabriel quiver of a wedge product of coalgebras and study the category of comodules of a semiprime coalgebra. In particular, we prove that any monomial semiprime k-tame fc-tame coalgebra is string. We also prove a version of Eisenbud-Griffith theorem for coalgebras, namely, any hereditary semiprime strictly quasi-finite coalgebra is serial. 相似文献
910.
Endotoxins (also known as lipopolysaccharides (LPS)) are undesirable by products of recombinant proteins, purified from Escherichia coli. LPS can be considered stable under a wide range of temperature and pH, making their removal one of the most difficult tasks in downstream processes during protein purification. The inherent toxicity of LPS makes their removal an important step for the application of these proteins in several biological assays and for a safe parenteral administration. Immobilized metal affinity chromatography (IMAC) enables the affinity interactions between the metal ions (immobilized on the support through the chelating compound) and the target molecules, thus enabling high efficiency separation of the target molecules from other components present in a mixture. Affinity chromatography is applied with Ca2+ iminodiacetic acid (IDA) to remove most of the LPS contaminants from the end product (more than 90%). In this study, the adsorption of LPS on an IDA-Ca2+was investigated. The adsorption Freundlich isotherm of LPS-IDA-Ca2+provides a theoretical basis for LPS removal. It was found that LPS is bound mainly by interactions between the phosphate group in LPS and Ca2+ligands on the beads. The factors such as pH (4.0 or 5.5) and ionic strength (1.0 mol/L) are essential to obtain effective removal of LPS for contaminant levels between endotoxin’ concentration values less than 100 EU/mL and 100000 EU/mL. This new protocol represents a substantial advantage in time, effort, and production costs. 相似文献