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By optimizing pump power ratio between 1st order backward pump and 2nd order forward pump on discrete Raman amplifier, we demonstrated over 2dB noise figure improvement without excessive non-linearity degradation.  相似文献   
3.
In a light-to-photocurrent conversion system based on a C60-porphyrin bilayer prepared by electrostatic alternate adsorption, porphyrin units in a porphyrin polymer have been isolated by cyclodextrin utilizing the host-guest interaction. In this system, a high quantum yield was achieved by suppression of self-quenching of porphyrin units.  相似文献   
4.
The calixarene-fullerene interaction,which causes only a slight change in the absorptionspectra, has been substantiated by calorimetricmeasurements: the H° values arecomparable with those obtained from the associationconstants estimated by a spectroscopic method. Furthermore, we determined the association constantbetween homooxacalix[3]arene and [60]fullerenederivatives with a porphyrin moiety by fluorescencespectra.  相似文献   
5.
A new series of BINOL-based macrocycles with two phenolic protons have been synthesized via oxidative coupling reaction using CuCl(OH)-TMEDA.  相似文献   
6.
8-Amino-s-triazolo[4, 3-b]pyridazine (I), an adenine analog has been prepared by two different routes. Likewise 8-amino-3-phenyl-s-triazolo[4,3-b]pyridazine (V) has been prepared. Both of these compounds have been prepared utilizing 3,4,5-trichloropyridazine and 3,4,6-trichloropyridazine as the starting materials thus interrelating the 3,4,5-and the 3,4,6-series. A variety of other transformations have been carried out.  相似文献   
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Tricyclo[3.3.1.1]decanone azine ( adamantanone azine ) reacts with 4-substituted 1,2,4-triazoline-3,5-diones under elimination of diazo adamantane to give a 1,3-dipole ( “azomethinimine” ), which on treatment with dipolahophiles affords the [ 2 + 3] -cycloadducts. The reaction is compared with singlet oxygen oxidation.  相似文献   
9.
The heat capacities of binary aqueous solutions of 1,2-ethanediol, 1,2-propanediol and 1,2-butanediol were measured at temperatures ranging from 283.15 to 338.15 K by differential scanning calorimetry. The partial molar heat capacities at the infinite dilution were then calculated for the respective alkanediols. For 1,2-ethanediol or 1,2-propanediol, the partial molar heat capacities at the infinite dilution of increased with increasing temperature. In contrast, the partial molar heat capacities of 1,2-butanediol at the infinite dilution decreased with increasing temperature. Heat capacity changes by dissolution of the alkanediols were also determined. Heat capacity changes caused by the dissolution of 1,2-ethanediol or 1,2-propanediol were increase with increasing temperature. On the other hand, heat capacity changes caused by the dissolution of 1,2-butanediol are decrease with increasing temperature. Thus our results indicated that the structural changes of water caused by the dissolution of 1,2-butanediol differed from that of the two other alkanediols. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
Proton T1 measurement with the Fourier transform method combined with quenching of dipolar coupling through selective deuterium substitution is shown to be a useful method for elucidating intra- and intermolecular interactions in solution, with 2′,3′-isopropylideneadenosine as an example. Average distances between H-8 and ribose protons are determine in combination with carbon-13 T1 measurement. The method is compared with the nuclear Overhauser effect.  相似文献   
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