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71.
It was found that the photoelectrochemical performance and photocatalytic activity of rod-type TiO2 electrodes were affected by various post-calcination treatments, for example, calcination in NH3 or under vacuum. Post-calcination treatment in NH3 at 773 K was particularly effective in increasing the photoelectrochemical performance and photocatalytic activity of rod-type TiO2 electrodes. A unique photoelectrochemical circuit was constructed by connecting a rod-type TiO2 electrode to a Pt electrode through a silicon solar cell in which the negative bias was applied on the rod-type TiO2 electrode. It was found that the photoelectrochemical circuit can effectively oxidize ethanethiol in water into CO2.  相似文献   
72.
73.
We propose a novel framework for probabilistic evaluation of interconnectable capacity for wind power generation. This is based on mathematical modeling of load frequency control systems, which captures their nonlinear (saturation and rate limiting) dynamical characteristics, and stochastic uncertainty of wind power output deviation. The method called stochastic linearization is used to analyze resulting power quality. The effectiveness of the proposed method is examined by numerical simulation.  相似文献   
74.
For a hyperbolic knot in , a toroidal surgery is Dehn surgery which yields a -manifold containing an incompressible torus. It is known that a toroidal surgery on is an integer or a half-integer. In this paper, we prove that all integers occur among the toroidal slopes of hyperbolic knots with bridge index at most three and tunnel number one.

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75.
The crystallization of 2,4,6-triethynyl-1,3,5-triazine (2) leads to a pi-stacked layered structure of a C(sp)-H...N hydrogen-bonded unique hexagonal network structure, which may be regarded as a supramolecular analogue of a hitherto unknown graphyne network: in-plane intermolecular interactions are short and linear H...N contacts (2.31 and 2.34 A) and the interlayer separation is 3.23 A.  相似文献   
76.
Linear logic, introduced by Girardet al., has a great power of expression, but no method for induction. This paper proposes a method of induction using knowledge represented by linear logical formulas. In linear logic, the number of propositions is controlled by logical operators. When a background theory and a hypothesis prove an example, the number of propositions on each side must be equivalent.  相似文献   
77.
78.
A simplified methodology for the building of prostaglandins substituted at the 10 and 11 positions is presented.  相似文献   
79.
We performed measurements of the optical reflectivity in the energy range 0.007–30 eV on the clathrate-VIII type compound α-Eu8Ga16- xGe30 x in order to investigate its electronic band structure. The very low charge carrier concentration as well as ferromagnetic ordering of the divalent Eu ions below 10.5 K characterize the spectra at photon energies below ≃0.4 eV in accordance with the results of band structure calculations. Disorder induced bound states have been identified to affect the optical conductivity at energies between 10 and 100 meV.  相似文献   
80.
The hydrothermally stable and long-range ordered Ce-MCM-48 and Fe-MCM-48 were conveniently synthesized at 393 K for 24 h by directly adding fluoride ions to the initial gel without posttreatment and pH adjustment. The Ce-MCM-48 with a Si/Ce of 200 and 100, which were prepared by directly adding fluoride ions, could still maintain their mesoporous structures after refluxing in boiling water for 3 days. The incorporation of Ce into MCM-48 could enhance the hydrothermal stability of MCM-48 in the absence of fluoride ions; however, the incorporation of Fe into MCM-48 materials barely improved the hydrothermal stability of MCM-48 materials. The effect of adding NaF was much more efficient in enhancement of hydrothermal stability than that of the incorporation of Ce. The addition of fluoride ions mainly improves the degree of polymerization of silicates. The Ce(4+) ions in Ce-MCM-48 appear to be present partly in tetrahedral coordination in the framework and partly as CeO(2) particles on the surface of framework. The Ce positioned on the surface of pore walls and in the framework both provide the protection against water attack.  相似文献   
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