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991.
Hiroshi Suga Emiko Koyama Hideo Tokuhisa Kyoko Fujiwara Tohru Nakamura Yasushiro Nishioka Wataru Mizutani Takao Ishida 《Surface science》2007,601(1):68-75
The adsorption process, molecular arrangement and protonation behavior of self-assembled monolayers (SAMs) of bipyridine thiol on Au(1 1 1) were investigated using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM), with a view towards constructing a molecular ion sensor. When the bipyridine SAMs were immersed in a strong CF3SO3H solution for protonation of the bipyridine group, additional N(1s) XPS peaks were generated at higher binding peak positions where the origin of the peak was considered to be the N-H species. We further investigated the relationship between the immersion time for the SAMs and the probability of protonation. We observed a decrease in the probability of protonation with a longer immersion time for the SAMs. We consider that both the bipyridine molecular arrangements and the molecular density on the Au surface are crucial for controlling the probability of protonation based on the STM and XPS data. 相似文献
992.
Ohne Zusammenfassung 相似文献
993.
994.
A two-wavelength oscillation C02 laser was constructed for the differential absorption measurement of low concentrations of atmospheric trace molecules and pollution molecules. A diffraction grating was alternately angle-modulated for the two-branch oscillation using a single C02 laser. The output power of the two wavelengths was balanced to be equal. With these characteristics, the phase-sensitive detection technique can be applied to give highly sensitive detection of the received power difference, which is proportional to the absorption in the optical path of the transmitted beams. A differential absorption spectrometer was used to demonstrate the usefulness of this two-wavelength laser oscillation method incorporating the output power balancing technique. The concentration of ethylene molecules was detected in a calibration cell and was also measured in real time in the exhaust of a combustion engine. From these results it has been shown that this differential absorption scheme offers a minimum detectable absorption of approximately 0.8%. 相似文献
995.
Takao Nishizeki 《Discrete Mathematics》1980,30(3):305-307
We construct a maxima' planar graph which is 1-tough but nonhamiltonian. The graph is an answer to Chvátal's question on the existence of such a graph. 相似文献
996.
Takao Usami Yoshio Kosugi Tsugio Takeuchi 《Journal of Polymer Science.Polymer Physics》1979,17(8):1413-1416
Coisotactic shift contributions caused by sterically crowded isotactic side-chain alkyl groups are proposed for peak assignments of isotactic propylene/butene-1 copolymers. Previously disputed analyses of methine triads and PB tetrads of backbone methylene carbons (α,α′-CH2) have been verified using first-order Markovian distribution theory. Coisotactic shift contributions also account for the reverse order of the propylene-centered triads from that predicted by the Grant-Paul equation. 相似文献
997.
An exactly solvable model of a partially dissociated gas of homonuclear diatomic molecules is presented, and its thermodynamic properties are studied. 相似文献
998.
Properties of excited states in111,113,115Sb were investigated with the (p, 2nγ) reaction. Singlesγ-ray spectra, neutron-gamma- and gamma-gamma coincidences, excitation functions and half-lives were measured. The experimental results are interpreted with the unified model. Recently found rotational bands are also excited in these reactions. 相似文献
999.
1000.
A reaction of (trimethylsilylmethylene)dimethylphenylphosphorane, PhMe2PCHSiMe3 (I), with phenyl isocyanate affords a 2/1 insertion product, which results from insertion of phenyl isocyanate into both the CSi and CH bonds of I. By way of contrast, a reaction of isothiocyanate and carbon disulfide with I affords 1/1 products by insertion of these heterocumulenes into the CSi bond of I. In these reactions, Wittig-type elimination of dimethylphenylphosphine oxide or sulfide did not occur because of irreversible migrations of the trimethylsilyl group to the anionic centers of the Zwitterionic intermediates. 相似文献