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51.
X. K. Xia L. G. Yang Z. G. She C. L. Shao Z. J. Huang F. Liu Y. C. Lin S. N. Zhou 《Chemistry of Natural Compounds》2008,44(4):416-418
Two new acids 1 and 2, together with a known compound, purpactin A (3), were isolated from endophytic fungus No. ZZF13. Their structures were elucidated on the basis of 1D, 2D NMR, and HREIMS
spectra.
Published in Khimiya Prirodnykh Soedinenii, No. 4, pp.336-337, July-August, 2008. Original articlesubmitted April 24, 2007. 相似文献
52.
53.
Nonlinear Dynamics - This paper investigates the generation of some novel bursting patterns in active control oscillator with multiple time delays. We present the bursting patterns, including... 相似文献
54.
Hong She Wang Wei Xing Zhao 《中国化学快报》2011,22(8):911-914
An efficient magnesium bistrifluoromethanesulfonimide[Mg(NTf_2)_2]catalyzed hydroalkylation of aromatic olefins with 1,3- diketones under solvent-free conditions has been developed.The reactions proceed smoothly to give the desired products in good yields in short reaction times. 相似文献
55.
Swanson MI She YM Ens W Brown EG Coombs KM 《Rapid communications in mass spectrometry : RCM》2002,16(24):2317-2324
Mammalian reovirus is an enteric virus that contains a double-stranded RNA genome. The genome consists of ten RNA segments that encode eight structural and three non-structural proteins. The structural proteins form a double-layered structure. The innermost layer, called the core, consists of five proteins (lambda1, lambda2, lambda3, micro 2, and sigma2). Protein lambda3 is the RNA-dependent RNA polymerase (RdRp) and micro 2 is thought to be an RdRp cofactor. Translation of most reovirus proteins is known to commence at the first start codon. However, the translation initiation site of the viral core protein micro 2, encoded by the M1 RNA segment, has been in dispute. Although the theoretical molecular weight of micro 2 is 83 267 Da the actual molecular weight is unknown because micro 2 runs aberrantly in SDS-PAGE and has resisted characterization by Edman degradation, indicating that the amino terminus is post-translationally modified. In this study, we used proteolysis coupled with MALDI-Qq-TOFMS to determine that translation of micro 2 initiates at the first AUG codon, that its actual molecular weight approximates the theoretical value of 83 kDa, that the amino terminal methionine residue is removed, and that the next amino acid (alanine) is post-translationally acetylated. 相似文献
56.
Our velocity measurements on quasi-two-dimensional turbulent flow in a rapidly rotating annulus yield self-similar (scale-independent) probability distribution functions for longitudinal velocity differences, deltav(l) = v(x+l)-v(x). These distribution functions are strongly non-Gaussian, suggesting that the coherent vortices play a significant role. The structure functions <[deltav(l)](p)> approximately l(zeta)p exhibit anomalous scaling: zeta(p) = p / 2 rather than the expected zeta(p) = p / 3. Correspondingly, the energy spectrum is described by E(k) approximately k(-2) rather than the expected E(k) approximately k(-5/3). 相似文献
58.
To simplify the reconstruction calculation of a large-aperture digital hologram we propose a novel Fourier-transformation reconstruction algorithm. When the reconstructed wave is the same as or similar to the reference wave, the higher-order phase term of reconstruction can be compensated for. For example, the variation between the higher-order phase term and the aperture angle with a different field of view in in-line phase-shifting digital holography is analyzed. 相似文献
59.
Shamita Dutta Gupta Xiaotie She 《Proceedings of the American Mathematical Society》2000,128(8):2203-2212
In this paper, we obtain an Euler product with functional equation associated to a noncuspidal metaplectic form on the double cover of . Zagier's idea of Rankin-Selberg method is used to define the convolution of and the -function.
60.
We have created a one- (rather than two-) dimensional quasi-steady-state photorefractive spatial soliton induced by a laser beam instead of an applied electric field. The formation of this type of spatial soliton depends on the intensity of the self-trapped beam, which is different from quasi-steady-state spatial solitons reported in the literature. The optically induced spatial soliton can be exploited in all optical switching applications. 相似文献