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61.
Onk-StrictlyConvexandk-VerySmoothBanachSpacesZhangZihou(张子厚)(HuainanTelecisionUniversity,Huainan,Anhui,232001)Abstract:Inthis... 相似文献
62.
T. Iwaniec M. Mitrea C. Scott 《Proceedings of the American Mathematical Society》1996,124(5):1467-1471
We prove a bound for the -norm of harmonic forms in terms of certain -norms of their normal and tangential components. In turn, this is used to show the -norm equivalence of the normal and tangential components of harmonic forms on manifolds.
63.
酞菁氧钛的合成及晶型转化 总被引:4,自引:0,他引:4
酞菁氧钛以联环己烷为溶剂,以邻苯二脂及四氯化钛直接反应生成。其优点是便于分离及纯化。同时对各晶型的获得及晶型间的相互转化进行了研究,并以X-射线粉末衍射及FT-IR进行了表征,并记录了不同晶型的酞菁氧钛在室温硫化硅橡胶中的吸收光谱。 相似文献
64.
The ring conformation of 2-O-methyl-1,3,4,5-tetrakis-O-tert-butyldiphenylsilyl-myo-inositol was in a twist form both in solid state and in solution. This is the first observation of a stable twist conformer induced by the introduction of bulky silyl protecting groups. 相似文献
65.
An equation for determining the equilibrium association constant (KA) of cyclodextrin inclusion complex with fluorescence anisotropy is derived and used to determine KA of pyrene-B-cyclodextrin inclusion complex. The existing forms of cyclodextrin inclusion complex in solution, the interaction type of host with guest, and the possibility of application of B-cyclodextrin in the analysis of metal ions using naphthalene derivative as a ligand are discussed based on the equation derived along with the curve of fluorescence anisotropy versus cyclodextrin concentration of guest/cyclodextrin system. 相似文献
66.
煤的超临界醇萃取脱硫:Ⅲ.形态硫的变化 总被引:1,自引:0,他引:1
本文分别应用Mossbauer谱和XPS(X射线光电子能谱)技术考察不同反应 条件下固体产物中的无机硫和有机硫的形态变化,结果表明;在超临界醇萃取脱硫过程中,黄铁矿硫的转化反应如下:FeS2-FeS+Fe1-xS,,转化的数量和深度主要取决于反应温度。275℃时磁黄铁矿(Fe1-xS)形式为FeS1.101,450℃时为FeS1.085;有机硫基团中PhSH ,Ph2S和四氢噻吩较易脱除,Ph2S 相似文献
67.
A. N. Chekhlov 《Journal of Structural Chemistry》2005,46(2):376-380
Crystal and molecular structures of 2-hydroxyimino-3-methyl-4-nitro-2,5-dihydrothiophene-1,1-dioxide C5H6N2O5S (I) have been re-determined by single crystal X-ray diffraction analysis. The structure of I (space group P212121, a = 6.124(1) Å, b = 9.205(2) Å, c = 14.884(3) Å, Z = 4) was solved by the direct method and refined anisotropically in the full-matrix approximation to R = 0.064 using all 1756 measured independent reflections (automated diffractometer CAD-4, λCuKα, anomalous scattering taken into account). This study proves that the compound I contains a disordered group H-O-N=C, but not the isomeric nitrone group O←N(H)=C, as it has been concluded by the workers who pioneered single crystal X-ray diffraction study of I and erroneously took the second low-occupied oxygen position of the disordered hydroxyimine group for H at N atom. 相似文献
68.
Isolated polyfluorobenzene (PFB) molecules and their protonated forms are investigated by the AM1 method with full geometry optimization. The proton affinities of PFB are estimated for different protonated positions. The proton affinity of PFB averaged over all isomers is shown to decrease monotonically as the number of fluorine atoms in the molecule increases. The relative populations of different isomers of arenonium ions (AI) formed by PFB protonation are determined. From the calculated data, the value of + for the F atom in theipso-position is estimated as 1.00. The activation energies of the 1,2-hydrogen shifts in AI are calculated. The dependences of the proton affinity and the activation energies of 1,2-hydrogen shifts on the number of halogen atoms are found to have distinct characters for PFB and polychlorobenzenes. The physical reasons for these difference are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1878–1882, November, 1993. 相似文献
69.
Epoxy resins in the solid state, liquid state and during polymerisation were treated by microwave oxygen plasma and analysed by FTIR spectra. Curing, etching and oxidation kinetics of epoxy resin were observed. In the liquid resin and polymerising mixture the effect of structure modification was observed more intensively than in the case of solid sample due to a mixing process. A modification of bulk layers of liquid epoxy resin was observed under plasma action. The polymerisation reaction of epoxy resin with amine hardening agent can be released in plasma discharge at low pressure. 相似文献
70.
Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene (LDPE), ethylene copolymer and organoclay. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer. 相似文献