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91.
Atkinson IM Chartres JD Groth AM Lindoy LF Lowe MP Meehan GV 《Chemical communications (Cambridge, England)》2002,(20):2428-2429
A new second generation dendrimer incorporating nine S2N2-donor macrocyclic units that bind nine Pd(II) cations is reported. 相似文献
92.
Removal of or replacement of one of two phenylethyl sidearms on azalariats leads to clear evidence for cation-pi interactions with the remaining sidearm. 相似文献
93.
The cation N(2)H(7)(+) has been stabilized in a largely hydrophobic supramolecular environment and characterized in the solid state. The cation is situated in the bowl-shaped cavity of calix[4]arene. All of the hydrogen atoms are clearly discernible owing to high-quality X-ray data as well as lack of disorder and symmetry-imposed ambiguity. It appears that electrostatic interactions play a critical role in stabilizing the structure. 相似文献
94.
95.
J. Leonard und S. L. Malhotra 《Colloid and polymer science》1978,256(7):716
Ohne Zusammenfassung 相似文献
96.
Guided by the theory of Neveu and Schwartz spin is introduced into the dual string model by equipping each parton with a Dirac spin index. A nearest-neighbour spin-spin coupling is introduced. The continuum limit results in dual covariant amplitudes. The solutions show different characteristics depending on whether the total number of partons is even or odd. The first case yields the meson theory of Neveu and Schwartz. The odd case leads to a baryon model. The simplest meson-baryon amplitude is computed. All claims made about the properties of the system are based on the exact solution of the finite problem. 相似文献
97.
Leonard I. Grossweiner 《Photochemistry and photobiology》1968,8(5):411-417
Abstract— The current status of research on sensitized photoconductive effects in zinc oxide is reviewed. The various types of chemical and spectral photosensitization processes observed in polycrystalline specimens can be explained qualitatively with a generalized electron acceptor molecule (EAM) model. in which electronegative surface agents trap zinc oxide conduction electrons in the dark and illumination causes a release of the trapped electrons. The EAM may be an adsorbed gas or vapor, adsorbed dye molecules, or an aggregated dye film, depending on the particular photoeffect. 相似文献
98.
99.
The vibrational modes localized at the interface between two distinct crystals have been studied for a simple crystal model obeying all of the invariance conditions required for models used in studies of dynamical properties of crystal surfaces, and giving rise to Rayleigh surface waves. The two crystals are assumed to be semi-infinite simple cubic and to have the same lattice parameter a. They differ by their mass (M and MA) and the central force interactions between first (K and Ka) and second nearest neighbors and . The interface is obtained by coupling the (001) free surfaces of these distinct crystals by central force intractions (K'). We find that the variation of the interaction conditions (K') at the interface and of the parameter has the following qualitative effects on the properties of surface and bulk phonons. When (K') increases from zero to a finite value, the frequencies of the surface phonons increase and are splitted in the case of two identical crystals. One can say that the surface phonons are transformed into interface modes. For some values of and parameters these interface phonons may be admixed with bulk phonons and thus become virtual interface states. 相似文献
100.