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121.
Ohno O Chiba T Todoroki S Yoshimura H Maru N Maekawa K Imagawa H Yamada K Wakamiya A Suenaga K Uemura D 《Chemical communications (Cambridge, England)》2011,47(46):12453-12455
Novel sesquiterpene alkaloids, halichonines A (1), B (2), and C (3), were identified from the marine sponge Halichondria okadai Kadota. By spectroscopic analyses and synthesis, their structures were revealed to include a 6,6-bicyclic ring system and two prenylated amine moieties. In addition, 2 induced apoptosis in HL60 human leukemia cells. 相似文献
122.
Hideaki Kaneko Richard D. Noren Peter A. Padilla 《Journal of Computational and Applied Mathematics》1997,80(2):351-349
In this paper, we analyse the iterated collocation method for Hammerstein equations with smooth and weakly singular kernels. The paper expands the study which began in [16] concerning the superconvergence of the iterated Galerkin method for Hammerstein equations. We obtain in this paper a similar superconvergence result for the iterated collocation method for Hammerstein equations. We also discuss the discrete collocation method for weakly singular Hammerstein equations. Some discrete collocation methods for Hammerstein equations with smooth kernels were given previously in [3, 18]. 相似文献
123.
Hideaki Hioki Mizuki Fukutaka Miwa Kubo Mitsuaki Kodama Keiko Ideta 《Tetrahedron》2005,61(45):10643-10651
A new traceless linker was developed to synthesize a library of 42 compounds possessing an azomethine linkage using combinatorial solid-phase parallel synthesis. The loading of the substrates on a solid support and cleavage from the solid support were performed by an imine synthesis and by imine-exchanged process under mild conditions, respectively. Thioesters with a hydroxy group on the central core exhibited liquid crystalline properties with the widest transition temperatures in the library. 相似文献
124.
We performed selective excitations of the first- and second-excited Frenkel exciton states (Q- and B-excitons) with use of sub-40-fs and sub-5-fs visible laser pulses. The transient absorption signals exhibit oscillatory features associated with molecular vibrations. From an analysis of the spectral profiles of the phase and amplitude of the oscillation, the experimental result is well explained by the modulated transition dipole moment, which is caused by the dynamic intensity borrowing from the intense B-transition to the weak Q-transition. 相似文献
125.
Hideaki Matsuda 《Journal of polymer science. Part A, Polymer chemistry》1974,12(2):455-468
As difunctional compounds containing an ionic bond in the molecule, divalent metal salts (I) of mono(hydroxyethyl) phthalate were prepared in high purity and high yield. Mg and Ca were selected as divalent metal. Metal-containing polyurethanes containing ionic links in the main chain were synthesized by the polyaddition reaction of I or, I–glycols with diisocyanates. The polyurethane obtained were glassy materials or white powders, depending on the species of diisocyanates and glycols. Close agreement between observed and calculated values of metal content of the polyurethanes were obtained. The viscosities (in dimethyl-formamide) of the polyurethanes decreased markedly with increasing of metal content. Moreover, the decomposition temperatures were lowered by introduction of metals into the polyurethanes. However, the decomposition rates of metal-containing polyurethanes were lower than those of polyurethanes not containing metal. 相似文献
126.
K. Murasugi 《Topology and its Applications》1985,19(3):227-243
Let p be a prime and let L be a 2-component link in S3. We define a numerical invariant, called p-height of L, using a tower of successive p-fold branched cyclic coverings of L, and show, in particular, 2-height is algorithmically determined for any 2-component link. Some relationships between p-height and known link type invariants are also established. 相似文献
127.
128.
129.
Hideaki Sakai 《Annals of the Institute of Statistical Mathematics》1980,32(1):393-400
The effect of regularly missed observations on the estimation of parameters of an autoregressive (AR) process is investigated
by using the frequency domain method. For first order AR processes, numerical results are shown to see a behavior of variances
of the estimate due to the missed observations. In some cases, we can positively utilize the concept of missed observations
to decrease the variances if the number of observations is fixed but time instants at with the observations are made can be
changed. 相似文献
130.