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Nonlinear Dynamics - Rectangular flat-bottom liquid tanks known as tuned liquid dampers (TLDs) are often used as passive mechanical dampers. Sloped- and triangular-bottom TLDs have been reported to...  相似文献   
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Abstract

The title compound has long been known as an essential component of lipopolysaccharides (LPS) and capsular polysaccharides which exist in the outer membrane of Gram-negative bacteria. KDO has attracted additional attention as a consequence of some remarkable discoveries; i) mutants unable to produce KDO are non-viable.1 ii) KDO is not present in mammalian cells,2 iii) the 2-deoxy analog of β-KDO represents a new class of synthetic antimicrobial agent.3,4 Although syntheses of KDO have been reported by many groups,5–8 a more efficient synthetic method endowed with the potential for synthesis of not only complex glycoconjugates but also biologically significant analogs is required.  相似文献   
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We present a new numerical scheme for solving the advection equation and its application to Vlasov simulations. The scheme treats not only point values of a profile but also its zeroth to second order piecewise moments as dependent variables, for better conservation of the information entropy. We have developed one-and two-dimensional schemes and show that they provide quite accurate solutions within reasonable usage of computational resources compared to other existing schemes. The two-dimensional scheme can accurately solve the solid body rotation problem of a gaussian profile for more than hundred rotation periods with little numerical diffusion. This is crucially important for Vlasov simulations of magnetized plasmas. Applications of the one- and two-dimensional schemes to electrostatic and electromagnetic Vlasov simulations are presented with some benchmark tests.  相似文献   
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We have demonstrated InxGa1−xN epitaxial growth with InN mole fractions of x=0.07 to 0.17 on an m-plane ZnO substrate by metalorganic vapor phase epitaxy for the first time. The crystalline quality of the epilayers was found to be much higher than that of epilayers grown on a GaN template on an m-plane SiC substrate.  相似文献   
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Let K be either the rational number field \Bbb Q{\Bbb Q} or an imaginary quadratic field. We give irrationality results for the number q = ?n=1rn/(qn-rl)\theta=\sum_{n=1}^{\infty}{r^n}/(q^n-r^l), where q (∣q∣ > 1) is an integer in K, rK × (∣r∣ < ∣q∣), and 1 £ l ? \Bbb Z1\le l\in{\Bbb Z} with q n r l (n ≥ 1).  相似文献   
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A simple method to label oligosaccharides with a multifunctional fluorescent group was developed. Oligosaccharides were quantitatively labeled at their reducing termini with pyrene butanoic acid hydrazide. The pyrene-labeled oligosaccharides were successfully applied to fluorescence polarization measurements and ELISA at picomole quantity, which was not previously reached by other procedures. This labeling method should prove to be useful in a variety of aspects in glycobiology.  相似文献   
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