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971.
2—苯基接三唑衍生物的合成研究 总被引:4,自引:0,他引:4
本文报道了用D-阿拉伯-己醛糖脎合成糖接三唑的基本方法,并由此合成了一系列接三唑衍生物,元素分析、~1H-NMR,~(13)C-NMR确证了它们的结构。 相似文献
972.
A. Yu. Zhumar’ 《Journal of Applied Spectroscopy》1998,65(6):967-972
It is shown that replacement of the investigated surface of a leaf by the opposite one, as well as nonuniform content of chlorophyll
over a pile of leaves, may lead to a change in the form of spectra for the first derivatives of reflection coefficients of
leaves. A simplified model of the reflection of a leaf is used to explain the experimental results obtained.
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 6, pp. 921–925, November–December, 1998. 相似文献
973.
974.
We demonstrate that the process of matrix factorization provides a systematic mathematical method to investigate the Hamiltonian
structure of non-linear evolution equations characterized by hereditary operators with Nijenhuis property. 相似文献
975.
.9J.AnirnductionLetQbeaboundedsymmetricdomaininthecon1plexvectorspaceC",Oen,withBergman-Silovboundaryb,rthegroupofholomorphicautomorphismsofaandnitsisotropygroup.ItisknownthatDiscircularandstar-shapedwitl1respecttoOandbiscircular.ThegroupflistransitiveonbandbhasauniquenormalizedO-invariantmeasuredwithd(b)=1-Hua[2]constructedbygrouprepresentationtl1eoryasystem{%,}ofhomogeneouspolyno-l,J k-l\mails,k=O,l,..',v=l,..',))l*'nI*=('J k-l),coml>leteandorthogonalonnandortl1onor-malonb.ByH(Q)weden… 相似文献
976.
It was established that many crystalline molecular complexes composed of cationic surfactants such as CTAB and several phenolic derivatives were obtained from an appropriate concentrated solution system in which a remarkable viscoelasticity was developed. It is revealed that the molecular complexes have an unambiguous composition of 1:1 molar ratio of surfactants to phenolic additives. The molecular complexes also showed characteristic endothermicity of a degree that suggests the specimens to be single and a pure species. However, through repeated runs the thermal stability of the complexes seemed to be rather poor, as exhibited by a profile change in thermograms of DSC. 相似文献
977.
A Case Study on the Use of Fractional Derivatives: The Low-Frequency Viscoelastic Uni-Directional Behavior of Polyurethane Foam 总被引:1,自引:0,他引:1
A fractional derivative model of dissipative effects is combined with a nonlinear elastic model to model the response of polyurethane foam in quasi-static compression tests. A system identification method is developed based on a separation of the elastic and viscoelastic parts of the response, which is possible because of symmetries in the imposed deformation time-history. Simulations are used to evaluate the proposed identification method when noise is present in the response. The system identification technique is also applied with some success to experimental data taken from several compression experiments on two types of polyurethane foam blocks. 相似文献
978.
Followingthedevelopmentoffullerenefunctionalization',therehasbeenanincreasinginterestinthesynthesisofchiralfullerenederivativesfortheirpotentialapplicationintheareasofpharmaceuticalsandoptics'~'.Introductionofchiralityfromthechiralsubstituenttothefullerenecore3hasbeenestablishedtobeoneofthemostversatilemethodsforthechiralfullerenederivatives.Inthisway,chiralweresynthesizedbyVasellaetap.ThesynthesisandCDspectraoffullerene-peptideswerereportedbyPratoandco-workers',aswellasDiederich'sgroup'.Rec… 相似文献
979.
Ambroladze and Wallin have posed several problems, about balayage of measures, which arose from work on approximation by
polynomial and rational interpolation in the complex plane. These problems concern the possible coincidence of measures swept
onto a Jordan curve from the inner and outer domains. This paper describes when the desired balayage properties hold. 相似文献
980.
亚纯函数及其导数的唯一性 总被引:1,自引:0,他引:1
本文证明了如下结果:设k,n是两个正整数,a,b,w是三个有穷复数,满足an≠bn,wn=1.如果一开平面上的亚纯函数f(z)以及它的k阶导数f(k)(z)分担两个集合S1={awi| i=1,2,…, n} , S2={bwi| i=1,2,…,n},则f(z)≡tf(k)(z),其中tn=1. 相似文献